Update from https://crrev.com/317530

cc/trees/layer_tree_host_unittest.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host.h"
 
 #include <algorithm>
 
 #include "base/auto_reset.h"
 #include "base/synchronization/lock.h"
@@ skipping 1302 matching lines @@
 
 // TODO(sohanjg) : Remove it once impl-side painting ships everywhere.
 // Verify atomicity of commits and reuse of textures.
 class LayerTreeHostTestDirectRendererAtomicCommit : public LayerTreeHostTest {
  public:
   void InitializeSettings(LayerTreeSettings* settings) override {
     settings->renderer_settings.texture_id_allocation_chunk_size = 1;
     // Make sure partial texture updates are turned off.
     settings->max_partial_texture_updates = 0;
     // Linear fade animator prevents scrollbars from drawing immediately.
-    settings->scrollbar_animator = LayerTreeSettings::NoAnimator;
+    settings->scrollbar_animator = LayerTreeSettings::NO_ANIMATOR;
   }
 
   void SetupTree() override {
     layer_ = FakeContentLayer::Create(&client_);
     layer_->SetBounds(gfx::Size(10, 20));
 
     bool paint_scrollbar = true;
     bool has_thumb = false;
     scrollbar_ = FakePaintedScrollbarLayer::Create(
         paint_scrollbar, has_thumb, layer_->id());
@@ skipping 982 matching lines @@
   scoped_refptr<FakeContentLayer> child_layer1_;
   scoped_refptr<FakeContentLayer> child_layer2_;
   int num_commits_;
 };
 
 SINGLE_AND_MULTI_THREAD_NOIMPL_TEST_F(
     LayerTreeHostTestShutdownWithOnlySomeResourcesEvicted);
 
 class LayerTreeHostTestLCDChange : public LayerTreeHostTest {
  public:
-  class PaintClient : public FakeContentLayerClient {
-   public:
-    PaintClient() : paint_count_(0) {}
-
-    int paint_count() const { return paint_count_; }
-
-    void PaintContents(SkCanvas* canvas,
-                       const gfx::Rect& clip,
-                       PaintingControlSetting picture_control) override {
-      FakeContentLayerClient::PaintContents(canvas, clip, picture_control);
-      ++paint_count_;
-    }
-
-    scoped_refptr<DisplayItemList> PaintContentsToDisplayList(
-        const gfx::Rect& clip,
-        PaintingControlSetting picture_control) override {
-      NOTIMPLEMENTED();
-      return DisplayItemList::Create();
-    }
-
-    bool FillsBoundsCompletely() const override { return false; }
-
-   private:
-    int paint_count_;
-  };
-
   void SetupTree() override {
     num_tiles_rastered_ = 0;
 
-    scoped_refptr<Layer> root_layer;
-    if (layer_tree_host()->settings().impl_side_painting)
-      root_layer = PictureLayer::Create(&client_);
-    else
-      root_layer = ContentLayer::Create(&client_);
+    scoped_refptr<Layer> root_layer = PictureLayer::Create(&client_);
     client_.set_fill_with_nonsolid_color(true);
     root_layer->SetIsDrawable(true);
     root_layer->SetBounds(gfx::Size(10, 10));
     root_layer->SetContentsOpaque(true);
 
     layer_tree_host()->SetRootLayer(root_layer);
 
-    // The expecations are based on the assumption that the default
+    // The expectations are based on the assumption that the default
     // LCD settings are:
     EXPECT_TRUE(layer_tree_host()->settings().can_use_lcd_text);
-    EXPECT_FALSE(root_layer->can_use_lcd_text());
 
     LayerTreeHostTest::SetupTree();
   }
 
   void BeginTest() override { PostSetNeedsCommitToMainThread(); }
 
   void DidCommitAndDrawFrame() override {
     switch (layer_tree_host()->source_frame_number()) {
       case 1:
-        // The first update consists of a paint of the whole layer.
-        EXPECT_EQ(1, client_.paint_count());
-        // LCD text must have been enabled on the layer.
-        EXPECT_TRUE(layer_tree_host()->root_layer()->can_use_lcd_text());
         PostSetNeedsCommitToMainThread();
         break;
       case 2:
-        // Since nothing changed on layer, there should be no paint.
-        EXPECT_EQ(1, client_.paint_count());
-        // LCD text must not have changed.
-        EXPECT_TRUE(layer_tree_host()->root_layer()->can_use_lcd_text());
         // Change layer opacity that should trigger lcd change.
         layer_tree_host()->root_layer()->SetOpacity(.5f);
         break;
       case 3:
-        // LCD text doesn't require re-recording, so no painting should occur.
-        EXPECT_EQ(1, client_.paint_count());
-        // LCD text must have been disabled on the layer due to opacity.
-        EXPECT_FALSE(layer_tree_host()->root_layer()->can_use_lcd_text());
         // Change layer opacity that should not trigger lcd change.
         layer_tree_host()->root_layer()->SetOpacity(1.f);
         break;
       case 4:
-        // LCD text doesn't require re-recording, so no painting should occur.
-        EXPECT_EQ(1, client_.paint_count());
-        // Even though LCD text could be allowed.
-        EXPECT_TRUE(layer_tree_host()->root_layer()->can_use_lcd_text());
         EndTest();
         break;
     }
   }
 
   void NotifyTileStateChangedOnThread(LayerTreeHostImpl* host_impl,
                                       const Tile* tile) override {
     ++num_tiles_rastered_;
   }
 
   void DrawLayersOnThread(LayerTreeHostImpl* host_impl) override {
+    PictureLayerImpl* root_layer =
+        static_cast<PictureLayerImpl*>(host_impl->active_tree()->root_layer());
+    bool can_use_lcd_text =
+        host_impl->active_tree()->root_layer()->can_use_lcd_text();
     switch (host_impl->active_tree()->source_frame_number()) {
       case 0:
         // The first draw.
         EXPECT_EQ(1, num_tiles_rastered_);
+        EXPECT_TRUE(can_use_lcd_text);
+        EXPECT_TRUE(root_layer->RasterSourceUsesLCDText());
         break;
       case 1:
         // Nothing changed on the layer.
         EXPECT_EQ(1, num_tiles_rastered_);
+        EXPECT_TRUE(can_use_lcd_text);
+        EXPECT_TRUE(root_layer->RasterSourceUsesLCDText());
         break;
       case 2:
-        // LCD text was disabled, it should be re-rastered with LCD text off.
+        // LCD text was disabled; it should be re-rastered with LCD text off.
         EXPECT_EQ(2, num_tiles_rastered_);
+        EXPECT_FALSE(can_use_lcd_text);
+        EXPECT_FALSE(root_layer->RasterSourceUsesLCDText());
         break;
       case 3:
-        // LCD text was enabled but it's sticky and stays off.
+        // LCD text was enabled, but it's sticky and stays off.
         EXPECT_EQ(2, num_tiles_rastered_);
+        EXPECT_TRUE(can_use_lcd_text);
+        EXPECT_FALSE(root_layer->RasterSourceUsesLCDText());
         break;
     }
   }
 
   void AfterTest() override {}
 
  private:
-  PaintClient client_;
+  FakeContentLayerClient client_;
   int num_tiles_rastered_;
 };
 
 SINGLE_AND_MULTI_THREAD_IMPL_TEST_F(LayerTreeHostTestLCDChange);
 
 // Verify that the BeginFrame notification is used to initiate rendering.
 class LayerTreeHostTestBeginFrameNotification : public LayerTreeHostTest {
  public:
   void InitializeSettings(LayerTreeSettings* settings) override {
     settings->use_external_begin_frame_source = true;
@@ skipping 3837 matching lines @@
   }
 
   void AfterTest() override { EXPECT_TRUE(did_commit_); }
 
  private:
   bool did_commit_;
 };
 
 SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostTestNoTasksBetweenWillAndDidCommit);
 
+// Verify that if a LayerImpl holds onto a copy request for multiple
+// frames that it will continue to have a render surface through
+// multiple commits, even though the Layer itself has no reason
+// to have a render surface.
+class LayerPreserveRenderSurfaceFromOutputRequests : public LayerTreeHostTest {
+ protected:
+  void SetupTree() override {
+    scoped_refptr<Layer> root = Layer::Create();
+    root->CreateRenderSurface();
+    root->SetBounds(gfx::Size(10, 10));
+    child_ = Layer::Create();
+    child_->SetBounds(gfx::Size(20, 20));
+    root->AddChild(child_);
+
+    layer_tree_host()->SetRootLayer(root);
+    LayerTreeHostTest::SetupTree();
+  }
+
+  static void CopyOutputCallback(scoped_ptr<CopyOutputResult> result) {}
+
+  void BeginTest() override {
+    child_->RequestCopyOfOutput(
+        CopyOutputRequest::CreateBitmapRequest(base::Bind(CopyOutputCallback)));
+    EXPECT_TRUE(child_->HasCopyRequest());
+    PostSetNeedsCommitToMainThread();
+  }
+
+  void DidCommit() override { EXPECT_FALSE(child_->HasCopyRequest()); }
+
+  void CommitCompleteOnThread(LayerTreeHostImpl* host_impl) override {
+    LayerImpl* child_impl = host_impl->sync_tree()->LayerById(child_->id());
+
+    switch (host_impl->sync_tree()->source_frame_number()) {
+      case 0:
+        EXPECT_TRUE(child_impl->HasCopyRequest());
+        EXPECT_TRUE(child_impl->render_surface());
+        break;
+      case 1:
+        if (host_impl->proxy()->CommitToActiveTree()) {
+          EXPECT_TRUE(child_impl->HasCopyRequest());
+          EXPECT_TRUE(child_impl->render_surface());
+        } else {
+          EXPECT_FALSE(child_impl->HasCopyRequest());
+          EXPECT_FALSE(child_impl->render_surface());
+        }
+        break;
+      default:
+        NOTREACHED();
+        break;
+    }
+  }
+
+  void DidActivateTreeOnThread(LayerTreeHostImpl* host_impl) override {
+    LayerImpl* child_impl = host_impl->active_tree()->LayerById(child_->id());
+    EXPECT_TRUE(child_impl->HasCopyRequest());
+    EXPECT_TRUE(child_impl->render_surface());
+
+    switch (host_impl->active_tree()->source_frame_number()) {
+      case 0:
+        // Lose output surface to prevent drawing and cause another commit.
+        host_impl->DidLoseOutputSurface();
+        break;
+      case 1:
+        EndTest();
+        break;
+      default:
+        NOTREACHED();
+        break;
+    }
+  }
+
+  void AfterTest() override {}
+
+ private:
+  scoped_refptr<Layer> child_;
+};
+
+SINGLE_AND_MULTI_THREAD_TEST_F(LayerPreserveRenderSurfaceFromOutputRequests);
+
 }  // namespace cc