cc: Simplify picture layer tiling update tile priorities.

cc/resources/picture_layer_tiling.h

Index: cc/resources/picture_layer_tiling.h
diff --git a/cc/resources/picture_layer_tiling.h b/cc/resources/picture_layer_tiling.h
index f4c5e7c405af9d60d0fa7b6628c5ff15a382a933..4c168e5666482e9e2c4fd213a323ebd515c94ddd 100644
--- a/cc/resources/picture_layer_tiling.h
+++ b/cc/resources/picture_layer_tiling.h
@@ -135,15 +135,9 @@ class CC_EXPORT PictureLayerTiling {
 
   void UpdateTilePriorities(
       WhichTree tree,
-      const gfx::Size& device_viewport,
       const gfx::Rect& viewport_in_layer_space,
       const gfx::Rect& visible_layer_rect,
-      const gfx::Size& last_layer_bounds,
-      const gfx::Size& current_layer_bounds,
-      float last_layer_contents_scale,
-      float current_layer_contents_scale,
-      const gfx::Transform& last_screen_transform,
-      const gfx::Transform& current_screen_transform,
+      float layer_contents_scale,
       double current_frame_time_in_seconds,
       size_t max_tiles_for_interest_area);

[enne (OOO), 2014/01/31 23:07:46]

This isn't part of your patch, but we don't change this at runtime in practice,
right? Could this be a constructor or other setter parameter?

(I'm happy with how few parameters get passed to this function and so I'm
itching to remove even more.)

[vmpstr, 2014/02/03 20:27:24]

Done. But to avoid passing this in other functions that create a tiling, I made
this a getter on the client. Personally, I like that better, but let me know.

 
@@ -198,6 +192,13 @@ class CC_EXPORT PictureLayerTiling {
   void SetLiveTilesRect(const gfx::Rect& live_tiles_rect);
   void CreateTile(int i, int j, const PictureLayerTiling* twin_tiling);
 
+  gfx::Rect ComputeVisibleRect(const gfx::Rect& viewport_in_layer_space,
+                               const gfx::Rect& visible_layer_rect) const;
+
+  gfx::Rect ComputeSkewport(double current_frame_time_in_seconds,
+                            const gfx::Rect& visible_rect_in_content_space)
+      const;
+
   // Given properties.
   float contents_scale_;
   gfx::Size layer_bounds_;
@@ -211,6 +212,7 @@ class CC_EXPORT PictureLayerTiling {
 
   // State saved for computing velocities based upon finite differences.
   double last_impl_frame_time_in_seconds_;
+  gfx::RectF last_visible_rect_in_content_space_;
 
   friend class CoverageIterator;