Fix UpdateTilePriorities viewport in Android WebView.

cc/trees/layer_tree_impl.h

Index: cc/trees/layer_tree_impl.h
diff --git a/cc/trees/layer_tree_impl.h b/cc/trees/layer_tree_impl.h
index 4dfc51110520c23755ce58e142d3b5ec135e4cd9..7b0011c2c8455ab20e15aef8a70942f79f595348 100644
--- a/cc/trees/layer_tree_impl.h
+++ b/cc/trees/layer_tree_impl.h
@@ -66,6 +66,7 @@ class CC_EXPORT LayerTreeImpl {
   FrameRateCounter* frame_rate_counter() const;
   PaintTimeCounter* paint_time_counter() const;
   MemoryHistory* memory_history() const;
+  bool device_viewport_valid_for_tile_management() const;
   bool IsActiveTree() const;
   bool IsPendingTree() const;
   bool IsRecycleTree() const;
@@ -77,6 +78,7 @@ class CC_EXPORT LayerTreeImpl {
   base::Time CurrentFrameTime() const;
   base::TimeTicks CurrentPhysicalTimeTicks() const;
   void SetNeedsCommit();
+  gfx::Rect DeviceViewport() const;
 
   // Tree specific methods exposed to layer-impl tree.
   // ---------------------------------------------------------------------------
@@ -86,7 +88,6 @@ class CC_EXPORT LayerTreeImpl {
   // trivial accessors in a followup patch.
   const LayerTreeDebugState& debug_state() const;
   float device_scale_factor() const;
-  gfx::Size device_viewport_size() const;
   DebugRectHistory* debug_rect_history() const;
   scoped_ptr<base::Value> AsValue() const;