cc: Expand invalidation to full tile when recording is missing for the tile.

cc/resources/picture_pile.h

 // Copyright 2012 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.
 
 #ifndef CC_RESOURCES_PICTURE_PILE_H_
 #define CC_RESOURCES_PICTURE_PILE_H_
 
 #include "cc/resources/picture_pile_base.h"
 #include "ui/gfx/rect.h"
 
 namespace cc {
 class PicturePileImpl;
 class Region;
 class RenderingStatsInstrumentation;
 
 class CC_EXPORT PicturePile : public PicturePileBase {
  public:
   PicturePile();
 
   // Re-record parts of the picture that are invalid.
-  // Invalidations are in layer space.
+  // Invalidations are in layer space, and will be expanded to cover everything
+  // that was either recorded/changed or that has no recording, leaving out only
+  // pieces that we had a recording for and it was not changed.
   // Return true iff the pile was modified.
-  bool Update(ContentLayerClient* painter,
-              SkColor background_color,
-              bool contents_opaque,
-              bool contents_fill_bounds_completely,
-              const Region& invalidation,
-              const gfx::Rect& visible_layer_rect,
-              int frame_number,
-              Picture::RecordingMode recording_mode,
-              RenderingStatsInstrumentation* stats_instrumentation);
+  bool UpdateAndExpandInvalidation(
+      ContentLayerClient* painter,
+      Region* invalidation,
+      SkColor background_color,
+      bool contents_opaque,
+      bool contents_fill_bounds_completely,
+      const gfx::Rect& visible_layer_rect,
+      int frame_number,
+      Picture::RecordingMode recording_mode,
+      RenderingStatsInstrumentation* stats_instrumentation);
 
   void set_slow_down_raster_scale_factor(int factor) {
     slow_down_raster_scale_factor_for_debug_ = factor;
   }
 
   void set_show_debug_picture_borders(bool show) {
     show_debug_picture_borders_ = show;
   }
 
   bool is_suitable_for_gpu_rasterization() const {
@@ skipping 10 matching lines @@
   friend class PicturePileImpl;
 
   bool is_suitable_for_gpu_rasterization_;
 
   DISALLOW_COPY_AND_ASSIGN(PicturePile);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_PICTURE_PILE_H_