Update from https://crrev.com/304121

cc/resources/picture_pile_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <map>
 #include <utility>
 
 #include "cc/resources/picture_pile.h"
 #include "cc/test/fake_content_layer_client.h"
-#include "cc/test/fake_rendering_stats_instrumentation.h"
+#include "cc/test/fake_picture_pile.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/geometry/size_conversions.h"
 
 namespace cc {
 namespace {
 
-class TestPicturePile : public PicturePile {
- public:
-  ~TestPicturePile() override {}
-
-  using PicturePile::buffer_pixels;
-  using PicturePile::CanRasterSlowTileCheck;
-  using PicturePile::Clear;
-
-  PictureMap& picture_map() { return picture_map_; }
-  const gfx::Rect& recorded_viewport() const { return recorded_viewport_; }
-
-  bool CanRasterLayerRect(const gfx::Rect& layer_rect) {
-    return CanRaster(1.f, layer_rect);
-  }
-
-  typedef PicturePile::PictureInfo PictureInfo;
-  typedef PicturePile::PictureMapKey PictureMapKey;
-  typedef PicturePile::PictureMap PictureMap;
-};
-
 class PicturePileTestBase {
  public:
   PicturePileTestBase()
       : background_color_(SK_ColorBLUE),
         min_scale_(0.125),
         frame_number_(0),
         contents_opaque_(false) {}
 
   void InitializeData() {
     pile_.SetTileGridSize(gfx::Size(1000, 1000));
     pile_.SetMinContentsScale(min_scale_);
     client_ = FakeContentLayerClient();
     SetTilingSize(pile_.tiling().max_texture_size());
   }
 
   void SetTilingSize(const gfx::Size& tiling_size) {
     Region invalidation;
     gfx::Rect viewport_rect(tiling_size);
     UpdateAndExpandInvalidation(&invalidation, tiling_size, viewport_rect);
   }
 
-  gfx::Size tiling_size() const { return pile_.tiling_size(); }
-  gfx::Rect tiling_rect() const { return gfx::Rect(pile_.tiling_size()); }
+  gfx::Size tiling_size() const { return pile_.GetSize(); }
+  gfx::Rect tiling_rect() const { return gfx::Rect(pile_.GetSize()); }
 
   bool UpdateAndExpandInvalidation(Region* invalidation,
                                    const gfx::Size& layer_size,
                                    const gfx::Rect& visible_layer_rect) {
     frame_number_++;
-    return pile_.UpdateAndExpandInvalidation(&client_,
-                                             invalidation,
-                                             background_color_,
-                                             contents_opaque_,
-                                             false,
-                                             layer_size,
-                                             visible_layer_rect,
-                                             frame_number_,
-                                             Picture::RECORD_NORMALLY,
-                                             &stats_instrumentation_);
+    return pile_.UpdateAndExpandInvalidation(
+        &client_, invalidation, background_color_, contents_opaque_, false,
+        layer_size, visible_layer_rect, frame_number_,
+        Picture::RECORD_NORMALLY);
   }
 
   bool UpdateWholePile() {
     Region invalidation = tiling_rect();
-    bool result = UpdateAndExpandInvalidation(
-        &invalidation, tiling_size(), tiling_rect());
+    bool result = UpdateAndExpandInvalidation(&invalidation, tiling_size(),
+                                              tiling_rect());
     EXPECT_EQ(tiling_rect().ToString(), invalidation.ToString());
     return result;
   }
 
   FakeContentLayerClient client_;
-  FakeRenderingStatsInstrumentation stats_instrumentation_;
-  TestPicturePile pile_;
+  FakePicturePile pile_;
   SkColor background_color_;
   float min_scale_;
   int frame_number_;
   bool contents_opaque_;
 };
 
 class PicturePileTest : public PicturePileTestBase, public testing::Test {
  public:
   virtual void SetUp() override { InitializeData(); }
 };
 
 TEST_F(PicturePileTest, InvalidationOnTileBorderOutsideInterestRect) {
   // Don't expand the interest rect past what we invalidate.
-  pile_.SetPixelRecordDistanceForTesting(0);
+  pile_.SetPixelRecordDistance(0);
 
   gfx::Size tile_size(100, 100);
   pile_.tiling().SetMaxTextureSize(tile_size);
 
   gfx::Size pile_size(400, 400);
   SetTilingSize(pile_size);
 
   // We have multiple tiles.
   EXPECT_GT(pile_.tiling().num_tiles_x(), 2);
   EXPECT_GT(pile_.tiling().num_tiles_y(), 2);
@@ skipping 62 matching lines @@
 
 TEST_F(PicturePileTest, SmallInvalidateInflated) {
   // Invalidate something inside a tile.
   Region invalidate_rect(gfx::Rect(50, 50, 1, 1));
   UpdateAndExpandInvalidation(&invalidate_rect, tiling_size(), tiling_rect());
   EXPECT_EQ(gfx::Rect(50, 50, 1, 1).ToString(), invalidate_rect.ToString());
 
   EXPECT_EQ(1, pile_.tiling().num_tiles_x());
   EXPECT_EQ(1, pile_.tiling().num_tiles_y());
 
-  TestPicturePile::PictureInfo& picture_info =
-      pile_.picture_map().find(TestPicturePile::PictureMapKey(0, 0))->second;
+  FakePicturePile::PictureInfo& picture_info =
+      pile_.picture_map().find(FakePicturePile::PictureMapKey(0, 0))->second;
   // We should have a picture.
   EXPECT_TRUE(!!picture_info.GetPicture());
   gfx::Rect picture_rect = gfx::ScaleToEnclosedRect(
       picture_info.GetPicture()->LayerRect(), min_scale_);
 
   // The the picture should be large enough that scaling it never makes a rect
   // smaller than 1 px wide or tall.
   EXPECT_FALSE(picture_rect.IsEmpty()) << "Picture rect " <<
       picture_rect.ToString();
 }
 
 TEST_F(PicturePileTest, LargeInvalidateInflated) {
   // Invalidate something inside a tile.
   Region invalidate_rect(gfx::Rect(50, 50, 100, 100));
   UpdateAndExpandInvalidation(&invalidate_rect, tiling_size(), tiling_rect());
   EXPECT_EQ(gfx::Rect(50, 50, 100, 100).ToString(), invalidate_rect.ToString());
 
   EXPECT_EQ(1, pile_.tiling().num_tiles_x());
   EXPECT_EQ(1, pile_.tiling().num_tiles_y());
 
-  TestPicturePile::PictureInfo& picture_info =
-      pile_.picture_map().find(TestPicturePile::PictureMapKey(0, 0))->second;
+  FakePicturePile::PictureInfo& picture_info =
+      pile_.picture_map().find(FakePicturePile::PictureMapKey(0, 0))->second;
   EXPECT_TRUE(!!picture_info.GetPicture());
 
   int expected_inflation = pile_.buffer_pixels();
 
   const Picture* base_picture = picture_info.GetPicture();
-  gfx::Rect base_picture_rect(pile_.tiling_size());
+  gfx::Rect base_picture_rect(tiling_size());
   base_picture_rect.Inset(-expected_inflation, -expected_inflation);
   EXPECT_EQ(base_picture_rect.ToString(),
             base_picture->LayerRect().ToString());
 }
 
 TEST_F(PicturePileTest, InvalidateOnTileBoundaryInflated) {
   gfx::Size new_tiling_size =
-      gfx::ToCeiledSize(gfx::ScaleSize(pile_.tiling_size(), 2.f));
+      gfx::ToCeiledSize(gfx::ScaleSize(tiling_size(), 2.f));
   // This creates initial pictures.
   SetTilingSize(new_tiling_size);
 
   // Due to border pixels, we should have 3 tiles.
   EXPECT_EQ(3, pile_.tiling().num_tiles_x());
   EXPECT_EQ(3, pile_.tiling().num_tiles_y());
 
   // We should have 1/.125 - 1 = 7 border pixels.
   EXPECT_EQ(7, pile_.buffer_pixels());
   EXPECT_EQ(7, pile_.tiling().border_texels());
 
   // Invalidate everything to have a non zero invalidation frequency.
   UpdateWholePile();
 
   // Invalidate something just over a tile boundary by a single pixel.
   // This will invalidate the tile (1, 1), as well as 1 row of pixels in (1, 0).
   Region invalidate_rect(
       gfx::Rect(pile_.tiling().TileBoundsWithBorder(0, 0).right(),
                 pile_.tiling().TileBoundsWithBorder(0, 0).bottom() - 1,
                 50,
                 50));
   Region expected_invalidation = invalidate_rect;
   UpdateAndExpandInvalidation(&invalidate_rect, tiling_size(), tiling_rect());
   EXPECT_EQ(expected_invalidation.ToString(), invalidate_rect.ToString());
 
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureInfo& picture_info =
+      FakePicturePile::PictureInfo& picture_info =
           pile_.picture_map()
-              .find(TestPicturePile::PictureMapKey(i, j))
+              .find(FakePicturePile::PictureMapKey(i, j))
               ->second;
 
       // Expect (1, 1) and (1, 0) to be invalidated once more
       // than the rest of the tiles.
       if (i == 1 && (j == 0 || j == 1)) {
         EXPECT_FLOAT_EQ(
-            2.0f / TestPicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
+            2.0f / FakePicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
             picture_info.GetInvalidationFrequencyForTesting());
       } else {
         EXPECT_FLOAT_EQ(
-            1.0f / TestPicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
+            1.0f / FakePicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
             picture_info.GetInvalidationFrequencyForTesting());
       }
     }
   }
 }
 
 TEST_F(PicturePileTest, InvalidateOnFullLayer) {
   UpdateWholePile();
 
   // Everything was invalidated once so far.
   for (auto& it : pile_.picture_map()) {
     EXPECT_FLOAT_EQ(
-        1.0f / TestPicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
+        1.0f / FakePicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
         it.second.GetInvalidationFrequencyForTesting());
   }
 
   // Invalidate everything,
   Region invalidation = tiling_rect();
   UpdateAndExpandInvalidation(&invalidation, tiling_size(), tiling_rect());
 
   // Everything was invalidated again.
   for (auto& it : pile_.picture_map()) {
     EXPECT_FLOAT_EQ(
-        2.0f / TestPicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
+        2.0f / FakePicturePile::PictureInfo::INVALIDATION_FRAMES_TRACKED,
         it.second.GetInvalidationFrequencyForTesting());
   }
 }
 
 TEST_F(PicturePileTest, StopRecordingOffscreenInvalidations) {
   gfx::Size new_tiling_size =
-      gfx::ToCeiledSize(gfx::ScaleSize(pile_.tiling_size(), 4.f));
+      gfx::ToCeiledSize(gfx::ScaleSize(tiling_size(), 4.f));
   SetTilingSize(new_tiling_size);
 
   gfx::Rect viewport(tiling_size().width(), 1);
 
   // Update the whole pile until the invalidation frequency is high.
   for (int frame = 0; frame < 33; ++frame) {
     UpdateWholePile();
   }
 
   // Make sure we have a high invalidation frequency.
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureInfo& picture_info =
+      FakePicturePile::PictureInfo& picture_info =
           pile_.picture_map()
-              .find(TestPicturePile::PictureMapKey(i, j))
+              .find(FakePicturePile::PictureMapKey(i, j))
               ->second;
       EXPECT_FLOAT_EQ(1.0f, picture_info.GetInvalidationFrequencyForTesting())
           << "i " << i << " j " << j;
     }
   }
 
   // Update once more with a small viewport.
   Region invalidation(tiling_rect());
   UpdateAndExpandInvalidation(&invalidation, tiling_size(), viewport);
   EXPECT_EQ(tiling_rect().ToString(), invalidation.ToString());
 
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureInfo& picture_info =
+      FakePicturePile::PictureInfo& picture_info =
           pile_.picture_map()
-              .find(TestPicturePile::PictureMapKey(i, j))
+              .find(FakePicturePile::PictureMapKey(i, j))
               ->second;
       EXPECT_FLOAT_EQ(1.0f, picture_info.GetInvalidationFrequencyForTesting());
 
       // If the y far enough away we expect to find no picture (no re-recording
       // happened). For close y, the picture should change.
       if (j >= 2)
         EXPECT_FALSE(picture_info.GetPicture()) << "i " << i << " j " << j;
       else
         EXPECT_TRUE(picture_info.GetPicture()) << "i " << i << " j " << j;
     }
   }
 
   // Update a partial tile that doesn't get recorded. We should expand the
   // invalidation to the entire tiles that overlap it.
   Region small_invalidation =
       gfx::Rect(pile_.tiling().TileBounds(3, 4).x(),
                 pile_.tiling().TileBounds(3, 4).y() + 10,
                 1,
                 1);
   UpdateAndExpandInvalidation(&small_invalidation, tiling_size(), viewport);
   EXPECT_TRUE(small_invalidation.Contains(gfx::UnionRects(
       pile_.tiling().TileBounds(2, 4), pile_.tiling().TileBounds(3, 4))))
       << small_invalidation.ToString();
 
   // Now update with no invalidation and full viewport
   Region empty_invalidation;
-  UpdateAndExpandInvalidation(
-      &empty_invalidation, tiling_size(), tiling_rect());
+  UpdateAndExpandInvalidation(&empty_invalidation, tiling_size(),
+                              tiling_rect());
   EXPECT_EQ(Region().ToString(), empty_invalidation.ToString());
 
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureInfo& picture_info =
+      FakePicturePile::PictureInfo& picture_info =
           pile_.picture_map()
-              .find(TestPicturePile::PictureMapKey(i, j))
+              .find(FakePicturePile::PictureMapKey(i, j))
               ->second;
       // Expect the invalidation frequency to be less than 1, since we just
       // updated with no invalidations.
       EXPECT_LT(picture_info.GetInvalidationFrequencyForTesting(), 1.f);
 
       // We expect that there are pictures everywhere now.
       EXPECT_TRUE(picture_info.GetPicture()) << "i " << i << " j " << j;
     }
   }
 }
@@ skipping 10 matching lines @@
   EXPECT_FALSE(pile_.CanRasterLayerRect(rect));
   EXPECT_FALSE(pile_.CanRasterSlowTileCheck(rect));
 }
 
 TEST_F(PicturePileTest, FrequentInvalidationCanRaster) {
   // This test makes sure that if part of the page is frequently invalidated
   // and doesn't get re-recorded, then CanRaster is not true for any
   // tiles touching it, but is true for adjacent tiles, even if it
   // overlaps on borders (edge case).
   gfx::Size new_tiling_size =
-      gfx::ToCeiledSize(gfx::ScaleSize(pile_.tiling_size(), 4.f));
+      gfx::ToCeiledSize(gfx::ScaleSize(tiling_size(), 4.f));
   SetTilingSize(new_tiling_size);
 
   gfx::Rect tile01_borders = pile_.tiling().TileBoundsWithBorder(0, 1);
   gfx::Rect tile02_borders = pile_.tiling().TileBoundsWithBorder(0, 2);
   gfx::Rect tile01_noborders = pile_.tiling().TileBounds(0, 1);
   gfx::Rect tile02_noborders = pile_.tiling().TileBounds(0, 2);
 
   // Sanity check these two tiles are overlapping with borders, since this is
   // what the test is trying to repro.
   EXPECT_TRUE(tile01_borders.Intersects(tile02_borders));
@@ skipping 13 matching lines @@
   }
 
   // Update once more with a small viewport.
   gfx::Rect viewport(tiling_size().width(), 1);
   Region invalidation(tiling_rect());
   UpdateAndExpandInvalidation(&invalidation, tiling_size(), viewport);
   EXPECT_EQ(tiling_rect().ToString(), invalidation.ToString());
 
   // Sanity check some pictures exist and others don't.
   EXPECT_TRUE(pile_.picture_map()
-                  .find(TestPicturePile::PictureMapKey(0, 1))
+                  .find(FakePicturePile::PictureMapKey(0, 1))
                   ->second.GetPicture());
   EXPECT_FALSE(pile_.picture_map()
-                   .find(TestPicturePile::PictureMapKey(0, 2))
+                   .find(FakePicturePile::PictureMapKey(0, 2))
                    ->second.GetPicture());
 
   EXPECT_TRUE(pile_.CanRasterLayerRect(tile01_noborders));
   EXPECT_TRUE(pile_.CanRasterSlowTileCheck(tile01_noborders));
   EXPECT_FALSE(pile_.CanRasterLayerRect(tile02_noborders));
   EXPECT_FALSE(pile_.CanRasterSlowTileCheck(tile02_noborders));
 }
 
 TEST_F(PicturePileTest, NoInvalidationValidViewport) {
   // This test validates that the recorded_viewport cache of full tiles
   // is still valid for some use cases.  If it's not, it's a performance
   // issue because CanRaster checks will go down the slow path.
   EXPECT_TRUE(!pile_.recorded_viewport().IsEmpty());
 
   // No invalidation, same viewport.
   Region invalidation;
   UpdateAndExpandInvalidation(&invalidation, tiling_size(), tiling_rect());
   EXPECT_TRUE(!pile_.recorded_viewport().IsEmpty());
   EXPECT_EQ(Region().ToString(), invalidation.ToString());
 
   // Partial invalidation, same viewport.
   invalidation = gfx::Rect(0, 0, 1, 1);
   UpdateAndExpandInvalidation(&invalidation, tiling_size(), tiling_rect());
   EXPECT_TRUE(!pile_.recorded_viewport().IsEmpty());
   EXPECT_EQ(gfx::Rect(0, 0, 1, 1).ToString(), invalidation.ToString());
 
   // No invalidation, changing viewport.
   invalidation = Region();
-  UpdateAndExpandInvalidation(
-      &invalidation, tiling_size(), gfx::Rect(5, 5, 5, 5));
+  UpdateAndExpandInvalidation(&invalidation, tiling_size(),
+                              gfx::Rect(5, 5, 5, 5));
   EXPECT_TRUE(!pile_.recorded_viewport().IsEmpty());
   EXPECT_EQ(Region().ToString(), invalidation.ToString());
 }
 
 TEST_F(PicturePileTest, BigFullLayerInvalidation) {
   gfx::Size huge_layer_size(100000000, 100000000);
   gfx::Rect viewport(300000, 400000, 5000, 6000);
 
   // Resize the pile.
   Region invalidation;
@@ skipping 128 matching lines @@
   Region expected_invalidation;
 
   pile_.tiling().SetMaxTextureSize(gfx::Size(tile_size, tile_size));
   SetTilingSize(base_tiling_size);
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   UpdateAndExpandInvalidation(
       &invalidation,
       grow_down_tiling_size,
       CornerSinglePixelRect(corner, grow_down_tiling_size));
 
-  // We should have lost the recordings in the bottom row.
+  // We should have lost all of the recordings in the bottom row as none of them
+  // are in the current interest rect (which is either the above or below it).
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(8, pile_.tiling().num_tiles_y());
   for (int i = 0; i < 6; ++i) {
     for (int j = 0; j < 6; ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_EQ(j < 5, it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated all new pixels in the recording.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_down_tiling_size),
                                           gfx::Rect(base_tiling_size));
   // But the new pixels don't cover the whole bottom row.
   gfx::Rect bottom_row = gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
                                          pile_.tiling().TileBounds(5, 5));
   EXPECT_FALSE(expected_invalidation.Contains(bottom_row));
   // We invalidated the entire old bottom row.
   expected_invalidation.Union(bottom_row);
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation,
                               base_tiling_size,
                               CornerSinglePixelRect(corner, base_tiling_size));
 
-  // We should have lost the recordings that are now outside the tiling only.
+  // When shrinking, we should have lost all the recordings in the bottom row
+  // not touching the interest rect.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      EXPECT_EQ(j < 6, it != map.end() && it->second.GetPicture());
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
+      bool expect_tile;
+      switch (corner) {
+        case TOP_LEFT:
+        case TOP_RIGHT:
+          expect_tile = j < 5;
+          break;
+        case BOTTOM_LEFT:
+          // The interest rect in the bottom left tile means we'll record it.
+          expect_tile = j < 5 || (j == 5 && i == 0);
+          break;
+        case BOTTOM_RIGHT:
+          // The interest rect in the bottom right tile means we'll record it.
+          expect_tile = j < 5 || (j == 5 && i == 5);
+          break;
+      }
+      EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  expected_invalidation.Clear();
+  // When shrinking, the previously exposed region is invalidated.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_down_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  // The whole bottom row of tiles (except any with the interest rect) are
+  // dropped.
+  gfx::Rect bottom_row_minus_existing_corner = gfx::UnionRects(
+      pile_.tiling().TileBounds(0, 5), pile_.tiling().TileBounds(5, 5));
+  switch (corner) {
+    case TOP_LEFT:
+    case TOP_RIGHT:
+      // No tiles are kept in the changed region because it doesn't
+      // intersect with the interest rect.
+      break;
+    case BOTTOM_LEFT:
+      bottom_row_minus_existing_corner.Subtract(
+          pile_.tiling().TileBounds(0, 5));
+      break;
+    case BOTTOM_RIGHT:
+      bottom_row_minus_existing_corner.Subtract(
+          pile_.tiling().TileBounds(5, 5));
+      break;
+  }
+
+  expected_invalidation.Union(bottom_row_minus_existing_corner);
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(
       &invalidation,
       grow_right_tiling_size,
       CornerSinglePixelRect(corner, grow_right_tiling_size));
 
-  // We should have lost the recordings in the right column.
+  // We should have lost all of the recordings in the right column as none of
+  // them are in the current interest rect (which is either entirely left or
+  // right of it).
   EXPECT_EQ(8, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < 6; ++i) {
     for (int j = 0; j < 6; ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_EQ(i < 5, it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated all new pixels in the recording.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_right_tiling_size),
                                           gfx::Rect(base_tiling_size));
   // But the new pixels don't cover the whole right_column.
   gfx::Rect right_column = gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
                                            pile_.tiling().TileBounds(5, 5));
   EXPECT_FALSE(expected_invalidation.Contains(right_column));
   // We invalidated the entire old right column.
   expected_invalidation.Union(right_column);
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation,
                               base_tiling_size,
                               CornerSinglePixelRect(corner, base_tiling_size));
 
-  // We should have lost the recordings that are now outside the tiling only.
+  // When shrinking, we should have lost all the recordings in the right column
+  // not touching the interest rect.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      EXPECT_EQ(i < 6, it != map.end() && it->second.GetPicture());
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
+      bool expect_tile;
+      switch (corner) {
+        case TOP_LEFT:
+        case BOTTOM_LEFT:
+          // No tiles are kept in the changed region because it doesn't
+          // intersect with the interest rect.
+          expect_tile = i < 5;
+          break;
+        case TOP_RIGHT:
+          // The interest rect in the top right tile means we'll record it.
+          expect_tile = i < 5 || (j == 0 && i == 5);
+          break;
+        case BOTTOM_RIGHT:
+          // The interest rect in the bottom right tile means we'll record it.
+          expect_tile = i < 5 || (j == 5 && i == 5);
+          break;
+      }
+      EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  expected_invalidation.Clear();
+  // When shrinking, the previously exposed region is invalidated.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_right_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  // The whole right column of tiles (except for ones with the interest rect)
+  // are dropped.
+  gfx::Rect right_column_minus_existing_corner = gfx::UnionRects(
+      pile_.tiling().TileBounds(5, 0), pile_.tiling().TileBounds(5, 5));
+  switch (corner) {
+    case TOP_LEFT:
+    case BOTTOM_LEFT:
+      break;
+    case TOP_RIGHT:
+      right_column_minus_existing_corner.Subtract(
+          pile_.tiling().TileBounds(5, 0));
+      break;
+    case BOTTOM_RIGHT:
+      right_column_minus_existing_corner.Subtract(
+          pile_.tiling().TileBounds(5, 5));
+      break;
+  }
+  expected_invalidation.Union(right_column_minus_existing_corner);
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(
       &invalidation,
       grow_both_tiling_size,
       CornerSinglePixelRect(corner, grow_both_tiling_size));
 
   // We should have lost the recordings in the right column and bottom row.
   EXPECT_EQ(8, pile_.tiling().num_tiles_x());
   EXPECT_EQ(8, pile_.tiling().num_tiles_y());
   for (int i = 0; i < 6; ++i) {
     for (int j = 0; j < 6; ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_EQ(i < 5 && j < 5, it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated all new pixels in the recording.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_both_tiling_size),
                                           gfx::Rect(base_tiling_size));
-  // But the new pixels don't cover the whole right_column.
+  // But the new pixels don't cover the whole right column or bottom row.
   Region right_column_and_bottom_row =
       UnionRegions(gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
                                    pile_.tiling().TileBounds(5, 5)),
                    gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
                                    pile_.tiling().TileBounds(5, 5)));
   EXPECT_FALSE(expected_invalidation.Contains(right_column_and_bottom_row));
   // We invalidated the entire old right column and the old bottom row.
   expected_invalidation.Union(right_column_and_bottom_row);
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
-  UpdateAndExpandInvalidation(&invalidation, base_tiling_size, gfx::Rect());
+  UpdateAndExpandInvalidation(&invalidation, base_tiling_size,
+                              CornerSinglePixelRect(corner, base_tiling_size));
 
-  // We should have lost the recordings that are now outside the tiling only.
+  // We should have lost the recordings in the right column and bottom row,
+  // except where it intersects the interest rect.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      EXPECT_EQ(i < 6 && j < 6, it != map.end() && it->second.GetPicture());
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
+      bool expect_tile;
+      switch (corner) {
+        case TOP_LEFT:
+          expect_tile = i < 5 && j < 5;
+          break;
+        case TOP_RIGHT:
+          // The interest rect in the top right tile means we'll record it.
+          expect_tile = (i < 5 && j < 5) || (j == 0 && i == 5);
+          break;
+        case BOTTOM_LEFT:
+          // The interest rect in the bottom left tile means we'll record it.
+          expect_tile = (i < 5 && j < 5) || (j == 5 && i == 0);
+          break;
+        case BOTTOM_RIGHT:
+          // The interest rect in the bottom right tile means we'll record it.
+          expect_tile = (i < 5 && j < 5) || (j == 5 && i == 5);
+          break;
+      }
+      EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture())
+          << i << "," << j;
     }
   }
 
-  // No invalidation when shrinking.
-  expected_invalidation.Clear();
+  // We invalidated all previous pixels in the recording.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_both_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  // The whole right column and bottom row of tiles (except for ones with the
+  // interest rect) are dropped.
+  Region right_column_and_bottom_row_minus_existing_corner =
+      right_column_and_bottom_row;
+  switch (corner) {
+    case TOP_LEFT:
+      break;
+    case BOTTOM_LEFT:
+      right_column_and_bottom_row_minus_existing_corner.Subtract(
+          pile_.tiling().TileBounds(0, 5));
+      break;
+    case TOP_RIGHT:
+      right_column_and_bottom_row_minus_existing_corner.Subtract(
+          pile_.tiling().TileBounds(5, 0));
+      break;
+    case BOTTOM_RIGHT:
+      right_column_and_bottom_row_minus_existing_corner.Subtract(
+          pile_.tiling().TileBounds(5, 5));
+      break;
+  }
+  expected_invalidation.Union(
+      right_column_and_bottom_row_minus_existing_corner);
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 }
 
 TEST_P(PicturePileResizeCornerTest, SmallResizePileOutsideInterestRect) {
   Corner corner = GetParam();
 
   // This size chosen to be larger than the interest rect size, which is
   // at least kPixelDistanceToRecord * 2 in each dimension.
   int tile_size = 100000;
@@ skipping 12 matching lines @@
   Region expected_invalidation;
 
   pile_.tiling().SetMaxTextureSize(gfx::Size(tile_size, tile_size));
   SetTilingSize(base_tiling_size);
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
-  UpdateAndExpandInvalidation(
-      &invalidation,
-      grow_down_tiling_size,
-      CornerSinglePixelRect(corner, grow_down_tiling_size));
-
-  // We should have lost the recordings in the bottom row that do not intersect
-  // the interest rect.
-  EXPECT_EQ(6, pile_.tiling().num_tiles_x());
-  EXPECT_EQ(6, pile_.tiling().num_tiles_y());
-  for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
-    for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      bool expect_tile;
+  // In this test (unlike the large resize test), as all growing and shrinking
+  // happens within tiles, the resulting invalidation is symmetrical, so use
+  // this enum to repeat the test both ways.
+  enum ChangeDirection { GROW, SHRINK, LAST_DIRECTION = SHRINK };
+
+  // Grow downward.
+  for (int dir = 0; dir <= LAST_DIRECTION; ++dir) {
+    gfx::Size new_tiling_size =
+        dir == GROW ? grow_down_tiling_size : base_tiling_size;
+    UpdateWholePile();
+    UpdateAndExpandInvalidation(&invalidation, new_tiling_size,
+                                CornerSinglePixelRect(corner, new_tiling_size));
+
+    // We should have lost the recordings in the bottom row that do not
+    // intersect the interest rect.
+    EXPECT_EQ(6, pile_.tiling().num_tiles_x());
+    EXPECT_EQ(6, pile_.tiling().num_tiles_y());
+    for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
+      for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
+        FakePicturePile::PictureMapKey key(i, j);
+        FakePicturePile::PictureMap& map = pile_.picture_map();
+        FakePicturePile::PictureMap::iterator it = map.find(key);
+        bool expect_tile;
+        switch (corner) {
+          case TOP_LEFT:
+          case TOP_RIGHT:
+            expect_tile = j < 5;
+            break;
+          case BOTTOM_LEFT:
+            // The interest rect in the bottom left tile means we'll record it.
+            expect_tile = j < 5 || (j == 5 && i == 0);
+            break;
+          case BOTTOM_RIGHT:
+            // The interest rect in the bottom right tile means we'll record it.
+            expect_tile = j < 5 || (j == 5 && i == 5);
+            break;
+        }
+        EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture());
+      }
+    }
+
+    // We invalidated the bottom row outside the new interest rect. The tile
+    // that insects the interest rect in invalidated only on its newly
+    // exposed or previously exposed pixels.
+    if (dir == GROW) {
+      // Only calculate the expected invalidation while growing, as the tile
+      // bounds post-growing is the newly exposed / previously exposed sizes.
+      // Post-shrinking, the tile bounds are smaller, so can't be used.
       switch (corner) {
         case TOP_LEFT:
         case TOP_RIGHT:
-          expect_tile = j < 5;
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(0, 5), pile_.tiling().TileBounds(5, 5));
           break;
         case BOTTOM_LEFT:
-          // The interest rect in the bottom left tile means we'll record it.
-          expect_tile = j < 5 || (j == 5 && i == 0);
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(1, 5), pile_.tiling().TileBounds(5, 5));
+          expected_invalidation.Union(SubtractRects(
+              pile_.tiling().TileBounds(0, 5), gfx::Rect(base_tiling_size)));
           break;
         case BOTTOM_RIGHT:
-          // The interest rect in the bottom right tile means we'll record it.
-          expect_tile = j < 5 || (j == 5 && i == 5);
-          break;
-      }
-      EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture());
-    }
-  }
-
-  // We invalidated the bottom row outside the new interest rect. The tile that
-  // insects the interest rect in invalidated only on its new pixels.
-  switch (corner) {
-    case TOP_LEFT:
-    case TOP_RIGHT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
-                                              pile_.tiling().TileBounds(5, 5));
-      break;
-    case BOTTOM_LEFT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(1, 5),
-                                              pile_.tiling().TileBounds(5, 5));
-      expected_invalidation.Union(SubtractRects(pile_.tiling().TileBounds(0, 5),
-                                                gfx::Rect(base_tiling_size)));
-      break;
-    case BOTTOM_RIGHT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
-                                              pile_.tiling().TileBounds(4, 5));
-      expected_invalidation.Union(SubtractRects(pile_.tiling().TileBounds(5, 5),
-                                                gfx::Rect(base_tiling_size)));
-      break;
-  }
-  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
-  invalidation.Clear();
-
-  UpdateWholePile();
-  UpdateAndExpandInvalidation(&invalidation,
-                              base_tiling_size,
-                              CornerSinglePixelRect(corner, base_tiling_size));
-
-  // We should have lost nothing.
-  EXPECT_EQ(6, pile_.tiling().num_tiles_x());
-  EXPECT_EQ(6, pile_.tiling().num_tiles_y());
-  for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
-    for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      EXPECT_TRUE(it != map.end() && it->second.GetPicture());
-    }
-  }
-
-  // We invalidated nothing.
-  expected_invalidation.Clear();
-  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
-  invalidation.Clear();
-
-  UpdateWholePile();
-  UpdateAndExpandInvalidation(
-      &invalidation,
-      grow_right_tiling_size,
-      CornerSinglePixelRect(corner, grow_right_tiling_size));
-
-  // We should have lost the recordings in the right column.
-  EXPECT_EQ(6, pile_.tiling().num_tiles_x());
-  EXPECT_EQ(6, pile_.tiling().num_tiles_y());
-  for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
-    for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      bool expect_tile;
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(0, 5), pile_.tiling().TileBounds(4, 5));
+          expected_invalidation.Union(SubtractRects(
+              pile_.tiling().TileBounds(5, 5), gfx::Rect(base_tiling_size)));
+          break;
+      }
+    }
+    EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
+    invalidation.Clear();
+  }
+
+  // Grow right.
+  for (int dir = 0; dir <= LAST_DIRECTION; ++dir) {
+    gfx::Size new_tiling_size =
+        dir == GROW ? grow_right_tiling_size : base_tiling_size;
+    UpdateWholePile();
+    UpdateAndExpandInvalidation(&invalidation, new_tiling_size,
+                                CornerSinglePixelRect(corner, new_tiling_size));
+
+    // We should have lost the recordings in the right column.
+    EXPECT_EQ(6, pile_.tiling().num_tiles_x());
+    EXPECT_EQ(6, pile_.tiling().num_tiles_y());
+    for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
+      for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
+        FakePicturePile::PictureMapKey key(i, j);
+        FakePicturePile::PictureMap& map = pile_.picture_map();
+        FakePicturePile::PictureMap::iterator it = map.find(key);
+        bool expect_tile;
+        switch (corner) {
+          case TOP_LEFT:
+          case BOTTOM_LEFT:
+            expect_tile = i < 5;
+            break;
+          case TOP_RIGHT:
+            // The interest rect in the top right tile means we'll record it.
+            expect_tile = i < 5 || (j == 0 && i == 5);
+            break;
+          case BOTTOM_RIGHT:
+            // The interest rect in the bottom right tile means we'll record it.
+            expect_tile = i < 5 || (j == 5 && i == 5);
+            break;
+        }
+        EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture());
+      }
+    }
+
+    // We invalidated the right column outside the new interest rect. The tile
+    // that insects the interest rect in invalidated only on its new or
+    // previously exposed pixels.
+    if (dir == GROW) {
+      // Calculate the expected invalidation the first time through the loop.
       switch (corner) {
         case TOP_LEFT:
         case BOTTOM_LEFT:
-          expect_tile = i < 5;
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(5, 0), pile_.tiling().TileBounds(5, 5));
           break;
         case TOP_RIGHT:
-          // The interest rect in the top right tile means we'll record it.
-          expect_tile = i < 5 || (j == 0 && i == 5);
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(5, 1), pile_.tiling().TileBounds(5, 5));
+          expected_invalidation.Union(SubtractRects(
+              pile_.tiling().TileBounds(5, 0), gfx::Rect(base_tiling_size)));
           break;
         case BOTTOM_RIGHT:
-          // The interest rect in the bottom right tile means we'll record it.
-          expect_tile = i < 5 || (j == 5 && i == 5);
-          break;
-      }
-      EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture());
-    }
-  }
-
-  // We invalidated the right column outside the new interest rect. The tile
-  // that insects the interest rect in invalidated only on its new pixels.
-  switch (corner) {
-    case TOP_LEFT:
-    case BOTTOM_LEFT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
-                                              pile_.tiling().TileBounds(5, 5));
-      break;
-    case TOP_RIGHT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(5, 1),
-                                              pile_.tiling().TileBounds(5, 5));
-      expected_invalidation.Union(SubtractRects(pile_.tiling().TileBounds(5, 0),
-                                                gfx::Rect(base_tiling_size)));
-      break;
-    case BOTTOM_RIGHT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
-                                              pile_.tiling().TileBounds(5, 4));
-      expected_invalidation.Union(SubtractRects(pile_.tiling().TileBounds(5, 5),
-                                                gfx::Rect(base_tiling_size)));
-      break;
-  }
-  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
-  invalidation.Clear();
-
-  UpdateWholePile();
-  UpdateAndExpandInvalidation(&invalidation,
-                              base_tiling_size,
-                              CornerSinglePixelRect(corner, base_tiling_size));
-
-  // We should have lost nothing.
-  EXPECT_EQ(6, pile_.tiling().num_tiles_x());
-  EXPECT_EQ(6, pile_.tiling().num_tiles_y());
-  for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
-    for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      EXPECT_TRUE(it != map.end() && it->second.GetPicture());
-    }
-  }
-
-  // We invalidated nothing.
-  expected_invalidation.Clear();
-  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
-  invalidation.Clear();
-
-  UpdateWholePile();
-  UpdateAndExpandInvalidation(
-      &invalidation,
-      grow_both_tiling_size,
-      CornerSinglePixelRect(corner, grow_both_tiling_size));
-
-  // We should have lost the recordings in the right column and bottom row. The
-  // tile that insects the interest rect in invalidated only on its new pixels.
-  EXPECT_EQ(6, pile_.tiling().num_tiles_x());
-  EXPECT_EQ(6, pile_.tiling().num_tiles_y());
-  for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
-    for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      bool expect_tile;
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(5, 0), pile_.tiling().TileBounds(5, 4));
+          expected_invalidation.Union(SubtractRects(
+              pile_.tiling().TileBounds(5, 5), gfx::Rect(base_tiling_size)));
+          break;
+      }
+    }
+    EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
+    invalidation.Clear();
+  }
+
+  // Grow both.
+  for (int dir = 0; dir <= LAST_DIRECTION; ++dir) {
+    gfx::Size new_tiling_size =
+        dir == GROW ? grow_both_tiling_size : base_tiling_size;
+    UpdateWholePile();
+    UpdateAndExpandInvalidation(&invalidation, new_tiling_size,
+                                CornerSinglePixelRect(corner, new_tiling_size));
+
+    // We should have lost the recordings in the right column and bottom row.
+    // The tile that insects the interest rect in invalidated only on its new
+    // or previously exposed pixels.
+    EXPECT_EQ(6, pile_.tiling().num_tiles_x());
+    EXPECT_EQ(6, pile_.tiling().num_tiles_y());
+    for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
+      for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
+        FakePicturePile::PictureMapKey key(i, j);
+        FakePicturePile::PictureMap& map = pile_.picture_map();
+        FakePicturePile::PictureMap::iterator it = map.find(key);
+        bool expect_tile;
+        switch (corner) {
+          case TOP_LEFT:
+            expect_tile = i < 5 && j < 5;
+            break;
+          case TOP_RIGHT:
+            // The interest rect in the top right tile means we'll record it.
+            expect_tile = (i < 5 && j < 5) || (j == 0 && i == 5);
+            break;
+          case BOTTOM_LEFT:
+            // The interest rect in the bottom left tile means we'll record it.
+            expect_tile = (i < 5 && j < 5) || (j == 5 && i == 0);
+            break;
+          case BOTTOM_RIGHT:
+            // The interest rect in the bottom right tile means we'll record it.
+            expect_tile = (i < 5 && j < 5) || (j == 5 && i == 5);
+            break;
+        }
+        EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture())
+            << i << "," << j;
+      }
+    }
+
+    // We invalidated the right column and the bottom row outside the new
+    // interest rect. The tile that insects the interest rect in invalidated
+    // only on its new or previous exposed pixels.
+    if (dir == GROW) {
+      // Calculate the expected invalidation the first time through the loop.
       switch (corner) {
         case TOP_LEFT:
-          expect_tile = i < 5 && j < 5;
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(5, 0), pile_.tiling().TileBounds(5, 5));
+          expected_invalidation.Union(
+              gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
+                              pile_.tiling().TileBounds(5, 5)));
           break;
         case TOP_RIGHT:
-          // The interest rect in the top right tile means we'll record it.
-          expect_tile = (i < 5 && j < 5) || (j == 0 && i == 5);
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(5, 1), pile_.tiling().TileBounds(5, 5));
+          expected_invalidation.Union(
+              gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
+                              pile_.tiling().TileBounds(5, 5)));
+          expected_invalidation.Union(SubtractRects(
+              pile_.tiling().TileBounds(5, 0), gfx::Rect(base_tiling_size)));
           break;
         case BOTTOM_LEFT:
-          // The interest rect in the bottom left tile means we'll record it.
-          expect_tile = (i < 5 && j < 5) || (j == 5 && i == 0);
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(5, 0), pile_.tiling().TileBounds(5, 5));
+          expected_invalidation.Union(
+              gfx::UnionRects(pile_.tiling().TileBounds(1, 5),
+                              pile_.tiling().TileBounds(5, 5)));
+          expected_invalidation.Union(SubtractRects(
+              pile_.tiling().TileBounds(0, 5), gfx::Rect(base_tiling_size)));
           break;
         case BOTTOM_RIGHT:
-          // The interest rect in the bottom right tile means we'll record it.
-          expect_tile = (i < 5 && j < 5) || (j == 5 && i == 5);
-          break;
-      }
-      EXPECT_EQ(expect_tile, it != map.end() && it->second.GetPicture())
-          << i << "," << j;
-    }
-  }
-
-  // We invalidated the right column and the bottom row outside the new interest
-  // rect. The tile that insects the interest rect in invalidated only on its
-  // new pixels.
-  switch (corner) {
-    case TOP_LEFT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
-                                              pile_.tiling().TileBounds(5, 5));
-      expected_invalidation.Union(gfx::UnionRects(
-          pile_.tiling().TileBounds(0, 5), pile_.tiling().TileBounds(5, 5)));
-      break;
-    case TOP_RIGHT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(5, 1),
-                                              pile_.tiling().TileBounds(5, 5));
-      expected_invalidation.Union(gfx::UnionRects(
-          pile_.tiling().TileBounds(0, 5), pile_.tiling().TileBounds(5, 5)));
-      expected_invalidation.Union(SubtractRects(pile_.tiling().TileBounds(5, 0),
-                                                gfx::Rect(base_tiling_size)));
-      break;
-    case BOTTOM_LEFT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
-                                              pile_.tiling().TileBounds(5, 5));
-      expected_invalidation.Union(gfx::UnionRects(
-          pile_.tiling().TileBounds(1, 5), pile_.tiling().TileBounds(5, 5)));
-      expected_invalidation.Union(SubtractRects(pile_.tiling().TileBounds(0, 5),
-                                                gfx::Rect(base_tiling_size)));
-      break;
-    case BOTTOM_RIGHT:
-      expected_invalidation = gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
-                                              pile_.tiling().TileBounds(5, 4));
-      expected_invalidation.Union(gfx::UnionRects(
-          pile_.tiling().TileBounds(0, 5), pile_.tiling().TileBounds(4, 5)));
-      expected_invalidation.Union(SubtractRegions(
-          pile_.tiling().TileBounds(5, 5), gfx::Rect(base_tiling_size)));
-      break;
-  }
-  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
-  invalidation.Clear();
-
-  UpdateWholePile();
-  UpdateAndExpandInvalidation(&invalidation,
-                              base_tiling_size,
-                              CornerSinglePixelRect(corner, base_tiling_size));
-
-  // We should have lost nothing.
-  EXPECT_EQ(6, pile_.tiling().num_tiles_x());
-  EXPECT_EQ(6, pile_.tiling().num_tiles_y());
-  for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
-    for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
-      EXPECT_TRUE(it != map.end() && it->second.GetPicture());
-    }
-  }
-
-  // We invalidated nothing.
-  expected_invalidation.Clear();
-  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
-  invalidation.Clear();
+          expected_invalidation = gfx::UnionRects(
+              pile_.tiling().TileBounds(5, 0), pile_.tiling().TileBounds(5, 4));
+          expected_invalidation.Union(
+              gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
+                              pile_.tiling().TileBounds(4, 5)));
+          expected_invalidation.Union(SubtractRegions(
+              pile_.tiling().TileBounds(5, 5), gfx::Rect(base_tiling_size)));
+          break;
+      }
+    }
+    EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
+    invalidation.Clear();
+  }
 }
 
 INSTANTIATE_TEST_CASE_P(
     PicturePileResizeCornerTests,
     PicturePileResizeCornerTest,
     ::testing::Values(TOP_LEFT, TOP_RIGHT, BOTTOM_LEFT, BOTTOM_RIGHT));
 
 TEST_F(PicturePileTest, ResizePileInsideInterestRect) {
   // This size chosen to be small enough that all the rects below fit inside the
   // the interest rect, so they are smaller than kPixelDistanceToRecord in each
   // dimension.
   int tile_size = 100;
   gfx::Size base_tiling_size(5 * tile_size, 5 * tile_size);
   gfx::Size grow_down_tiling_size(5 * tile_size, 7 * tile_size);
   gfx::Size grow_right_tiling_size(7 * tile_size, 5 * tile_size);
   gfx::Size grow_both_tiling_size(7 * tile_size, 7 * tile_size);
 
   Region invalidation;
   Region expected_invalidation;
 
   pile_.tiling().SetMaxTextureSize(gfx::Size(tile_size, tile_size));
   SetTilingSize(base_tiling_size);
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   UpdateAndExpandInvalidation(
       &invalidation, grow_down_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(8, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated the newly exposed pixels on the bottom row of tiles.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_down_tiling_size),
                                           gfx::Rect(base_tiling_size));
   Region bottom_row_new_pixels =
       SubtractRegions(gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
                                       pile_.tiling().TileBounds(5, 5)),
                       gfx::Rect(base_tiling_size));
   EXPECT_TRUE(expected_invalidation.Contains(bottom_row_new_pixels));
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation, base_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  EXPECT_EQ(Region().ToString(), invalidation.ToString());
+  // We invalidated the previously exposed pixels on the bottom row of tiles.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_down_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  EXPECT_TRUE(expected_invalidation.Contains(bottom_row_new_pixels));
+  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(
       &invalidation, grow_right_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(8, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated the newly exposed pixels on the right column of tiles.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_right_tiling_size),
                                           gfx::Rect(base_tiling_size));
   Region right_column_new_pixels =
       SubtractRegions(gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
                                       pile_.tiling().TileBounds(5, 5)),
                       gfx::Rect(base_tiling_size));
   EXPECT_TRUE(expected_invalidation.Contains(right_column_new_pixels));
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation, base_tiling_size, gfx::Rect(1, 1));
 
   // We should have lost the recordings that are now outside the tiling only.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  EXPECT_EQ(Region().ToString(), invalidation.ToString());
+  // We invalidated the previously exposed pixels on the right column of tiles.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_right_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  EXPECT_TRUE(expected_invalidation.Contains(right_column_new_pixels));
+  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(
       &invalidation, grow_both_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(8, pile_.tiling().num_tiles_x());
   EXPECT_EQ(8, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated the newly exposed pixels on the bottom row and right column
   // of tiles.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_both_tiling_size),
                                           gfx::Rect(base_tiling_size));
   Region bottom_row_and_right_column_new_pixels = SubtractRegions(
       UnionRegions(gfx::UnionRects(pile_.tiling().TileBounds(0, 5),
                                    pile_.tiling().TileBounds(5, 5)),
                    gfx::UnionRects(pile_.tiling().TileBounds(5, 0),
                                    pile_.tiling().TileBounds(5, 5))),
       gfx::Rect(base_tiling_size));
   EXPECT_TRUE(
       expected_invalidation.Contains(bottom_row_and_right_column_new_pixels));
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation, base_tiling_size, gfx::Rect());
 
   // We should have lost the recordings that are now outside the tiling only.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  EXPECT_EQ(Region().ToString(), invalidation.ToString());
+  // We invalidated the previously exposed pixels on the bottom row and right
+  // column of tiles.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_both_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  EXPECT_TRUE(
+      expected_invalidation.Contains(bottom_row_and_right_column_new_pixels));
+  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 }
 
 TEST_F(PicturePileTest, SmallResizePileInsideInterestRect) {
   // This size chosen to be small enough that all the rects below fit inside the
   // the interest rect, so they are smaller than kPixelDistanceToRecord in each
   // dimension.
   int tile_size = 100;
   gfx::Size base_tiling_size(5 * tile_size, 5 * tile_size);
   gfx::Size grow_down_tiling_size(5 * tile_size, 5 * tile_size + 5);
   gfx::Size grow_right_tiling_size(5 * tile_size + 5, 5 * tile_size);
   gfx::Size grow_both_tiling_size(5 * tile_size + 5, 5 * tile_size + 5);
 
   Region invalidation;
   Region expected_invalidation;
 
   pile_.tiling().SetMaxTextureSize(gfx::Size(tile_size, tile_size));
   SetTilingSize(base_tiling_size);
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   UpdateAndExpandInvalidation(
       &invalidation, grow_down_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated the newly exposed pixels.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_down_tiling_size),
                                           gfx::Rect(base_tiling_size));
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation, base_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  EXPECT_EQ(Region().ToString(), invalidation.ToString());
+  // We invalidated the previously exposed pixels.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_down_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(
       &invalidation, grow_right_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated the newly exposed pixels.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_right_tiling_size),
                                           gfx::Rect(base_tiling_size));
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation, base_tiling_size, gfx::Rect(1, 1));
 
   // We should have lost the recordings that are now outside the tiling only.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  EXPECT_EQ(Region().ToString(), invalidation.ToString());
+  // We invalidated the previously exposed pixels.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_right_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(
       &invalidation, grow_both_tiling_size, gfx::Rect(1, 1));
 
   // We should have a recording for every tile.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
   // We invalidated the newly exposed pixels.
   expected_invalidation = SubtractRegions(gfx::Rect(grow_both_tiling_size),
                                           gfx::Rect(base_tiling_size));
   EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 
   UpdateWholePile();
   UpdateAndExpandInvalidation(&invalidation, base_tiling_size, gfx::Rect());
 
   // We should have lost the recordings that are now outside the tiling only.
   EXPECT_EQ(6, pile_.tiling().num_tiles_x());
   EXPECT_EQ(6, pile_.tiling().num_tiles_y());
   for (int i = 0; i < pile_.tiling().num_tiles_x(); ++i) {
     for (int j = 0; j < pile_.tiling().num_tiles_y(); ++j) {
-      TestPicturePile::PictureMapKey key(i, j);
-      TestPicturePile::PictureMap& map = pile_.picture_map();
-      TestPicturePile::PictureMap::iterator it = map.find(key);
+      FakePicturePile::PictureMapKey key(i, j);
+      FakePicturePile::PictureMap& map = pile_.picture_map();
+      FakePicturePile::PictureMap::iterator it = map.find(key);
       EXPECT_TRUE(it != map.end() && it->second.GetPicture());
     }
   }
 
-  // No invalidation when shrinking.
-  EXPECT_EQ(Region().ToString(), invalidation.ToString());
+  // We invalidated the previously exposed pixels.
+  expected_invalidation = SubtractRegions(gfx::Rect(grow_both_tiling_size),
+                                          gfx::Rect(base_tiling_size));
+  EXPECT_EQ(expected_invalidation.ToString(), invalidation.ToString());
   invalidation.Clear();
 }
 
 TEST_F(PicturePileTest, SolidRectangleIsSolid) {
   // If the client has no contents, the solid state will be true.
   Region invalidation1(tiling_rect());
   UpdateAndExpandInvalidation(&invalidation1, tiling_size(), tiling_rect());
   EXPECT_TRUE(pile_.is_solid_color());
   EXPECT_EQ(static_cast<SkColor>(SK_ColorTRANSPARENT), pile_.solid_color());
 
@@ skipping 55 matching lines @@
   gfx::Rect smallRect = visible_rect;
   smallRect.Inset(10, 10, 10, 10);
   client_.add_draw_rect(smallRect, paint);
   Region invalidation(visible_rect);
   UpdateAndExpandInvalidation(&invalidation, tiling_size, visible_rect);
   EXPECT_FALSE(pile_.is_solid_color());
 }
 
 TEST_F(PicturePileTest, SetEmptyBounds) {
   EXPECT_TRUE(pile_.is_solid_color());
-  EXPECT_FALSE(pile_.tiling_size().IsEmpty());
+  EXPECT_FALSE(pile_.GetSize().IsEmpty());
   EXPECT_FALSE(pile_.picture_map().empty());
   EXPECT_TRUE(pile_.HasRecordings());
   pile_.SetEmptyBounds();
   EXPECT_FALSE(pile_.is_solid_color());
-  EXPECT_TRUE(pile_.tiling_size().IsEmpty());
+  EXPECT_TRUE(pile_.GetSize().IsEmpty());
   EXPECT_TRUE(pile_.picture_map().empty());
   EXPECT_FALSE(pile_.HasRecordings());
 }
 
 }  // namespace
 }  // namespace cc