Update from https://crrev.com/309415

cc/layers/picture_layer_impl.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_LAYERS_PICTURE_LAYER_IMPL_H_
 #define CC_LAYERS_PICTURE_LAYER_IMPL_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 50 matching lines @@
                    AppendQuadsData* append_quads_data) override;
   void UpdateTiles(const Occlusion& occlusion_in_content_space,
                    bool resourceless_software_draw) override;
   void NotifyTileStateChanged(const Tile* tile) override;
   void DidBecomeActive() override;
   void DidBeginTracing() override;
   void ReleaseResources() override;
   skia::RefPtr<SkPicture> GetPicture() override;
 
   // PictureLayerTilingClient overrides.
-  scoped_refptr<Tile> CreateTile(PictureLayerTiling* tiling,
+  scoped_refptr<Tile> CreateTile(float contents_scale,
                                  const gfx::Rect& content_rect) override;
   gfx::Size CalculateTileSize(const gfx::Size& content_bounds) const override;
   const Region* GetPendingInvalidation() override;
   const PictureLayerTiling* GetPendingOrActiveTwinTiling(
       const PictureLayerTiling* tiling) const override;
   PictureLayerTiling* GetRecycledTwinTiling(
       const PictureLayerTiling* tiling) override;
   TilePriority::PriorityBin GetMaxTilePriorityBin() const override;
   WhichTree GetTree() const override;
   bool RequiresHighResToDraw() const override;
@@ skipping 16 matching lines @@
 
   // Functions used by tile manager.
   PictureLayerImpl* GetPendingOrActiveTwinLayer() const;
   bool IsOnActiveOrPendingTree() const;
   // Virtual for testing.
   virtual bool HasValidTilePriorities() const;
   bool AllTilesRequiredForActivationAreReadyToDraw() const;
   bool AllTilesRequiredForDrawAreReadyToDraw() const;
 
   // Used for benchmarking
-  const RasterSource* GetRasterSource() const { return raster_source_.get(); }
+  RasterSource* GetRasterSource() const { return raster_source_.get(); }
 
  protected:
   friend class LayerRasterTileIterator;
   using TileRequirementCheck = bool (PictureLayerTiling::*)(const Tile*) const;
 
   PictureLayerImpl(LayerTreeImpl* tree_impl, int id, bool is_mask);
   PictureLayerTiling* AddTiling(float contents_scale);
   void RemoveAllTilings();
   void AddTilingsForRasterScale();
   void UpdateTilePriorities(const Occlusion& occlusion_in_content_space);
   virtual bool ShouldAdjustRasterScale() const;
   virtual void RecalculateRasterScales();
   void CleanUpTilingsOnActiveLayer(
       std::vector<PictureLayerTiling*> used_tilings);
   float MinimumContentsScale() const;
+  float MaximumContentsScale() const;
   void ResetRasterScale();
   gfx::Rect GetViewportForTilePriorityInContentSpace() const;
   PictureLayerImpl* GetRecycledTwinLayer() const;
 
-  bool CanHaveTilingWithScale(float contents_scale) const;
   void SanityCheckTilingState() const;
   // Checks if all tiles required for a certain action (e.g. activation) are
   // ready to draw.  is_tile_required_callback gets called on all candidate
   // tiles and returns true if the tile is required for the action.
   bool AllTilesRequiredAreReadyToDraw(
       TileRequirementCheck is_tile_required_callback) const;
 
   bool ShouldAdjustRasterScaleDuringScaleAnimations() const;
 
   void GetDebugBorderProperties(SkColor* color, float* width) const override;
@@ skipping 38 matching lines @@
   // from regular draws. Save a copy of the required draw properties of the last
   // frame that has a valid viewport for prioritizing tiles.
   gfx::Rect visible_rect_for_tile_priority_;
 
   DISALLOW_COPY_AND_ASSIGN(PictureLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_PICTURE_LAYER_IMPL_H_