cc: Replace Region with SimpleEnclosedRegion for occlusion tracking

cc/resources/layer_tiling_data.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/resources/layer_tiling_data.h"
 
 #include <vector>
 
 #include "base/logging.h"
+#include "cc/base/region.h"
+#include "cc/base/simple_enclosed_region.h"
 
 namespace cc {
 
 scoped_ptr<LayerTilingData> LayerTilingData::Create(const gfx::Size& tile_size,
                                                     BorderTexelOption border) {
   return make_scoped_ptr(new LayerTilingData(tile_size, border));
 }
 
 LayerTilingData::LayerTilingData(const gfx::Size& tile_size,
                                  BorderTexelOption border)
@@ skipping 63 matching lines @@
   *right = tiling_data_.TileXIndexFromSrcCoord(content_rect.right() - 1);
   *bottom = tiling_data_.TileYIndexFromSrcCoord(content_rect.bottom() - 1);
 }
 
 gfx::Rect LayerTilingData::TileRect(const Tile* tile) const {
   gfx::Rect tile_rect = tiling_data_.TileBoundsWithBorder(tile->i(), tile->j());
   tile_rect.set_size(tile_size());
   return tile_rect;
 }
 
-Region LayerTilingData::OpaqueRegionInContentRect(
+SimpleEnclosedRegion LayerTilingData::OpaqueRegionInContentRect(
     const gfx::Rect& content_rect) const {
   if (content_rect.IsEmpty())
-    return Region();
+    return SimpleEnclosedRegion();
 
   Region opaque_region;
   int left, top, right, bottom;
   ContentRectToTileIndices(content_rect, &left, &top, &right, &bottom);
   for (int j = top; j <= bottom; ++j) {
     for (int i = left; i <= right; ++i) {
       Tile* tile = TileAt(i, j);
       if (!tile)
         continue;
 
       gfx::Rect tile_opaque_rect =
           gfx::IntersectRects(content_rect, tile->opaque_rect());
       opaque_region.Union(tile_opaque_rect);
     }
   }
-  return opaque_region;
+  return SimpleEnclosedRegion(opaque_region);
 }
 
 void LayerTilingData::SetTilingSize(const gfx::Size& tiling_size) {
   tiling_data_.SetTilingSize(tiling_size);
   if (tiling_size.IsEmpty()) {
     tiles_.clear();
     return;
   }
 
   // Any tiles completely outside our new bounds are invalid and should be
   // dropped.
   int left, top, right, bottom;
   ContentRectToTileIndices(
       gfx::Rect(tiling_size), &left, &top, &right, &bottom);
   std::vector<TileMapKey> invalid_tile_keys;
   for (TileMap::const_iterator it = tiles_.begin(); it != tiles_.end(); ++it) {
     if (it->first.first > right || it->first.second > bottom)
       invalid_tile_keys.push_back(it->first);
   }
   for (size_t i = 0; i < invalid_tile_keys.size(); ++i)
     tiles_.erase(invalid_tile_keys[i]);
 }
 
 }  // namespace cc