Revert of cc: Remove tile sharing from tilings.

cc/resources/tile.h

Index: cc/resources/tile.h
diff --git a/cc/resources/tile.h b/cc/resources/tile.h
index 45c2b0482fdd77414203a12d8e463c8e0b8f678d..dcc8566fe4b7692ec29a53ae0d9018f58c3b762c 100644
--- a/cc/resources/tile.h
+++ b/cc/resources/tile.h
@@ -31,13 +31,46 @@
 
   const RasterSource* raster_source() const { return raster_source_.get(); }
 
-  const TilePriority& priority() const { return priority_; }
+  const TilePriority& priority(WhichTree tree) const {
+    return priority_[tree];
+  }
 
-  void set_priority(const TilePriority& priority) { priority_ = priority; }
+  TilePriority priority_for_tree_priority(TreePriority tree_priority) const {
+    switch (tree_priority) {
+      case SMOOTHNESS_TAKES_PRIORITY:
+        return priority_[ACTIVE_TREE];
+      case NEW_CONTENT_TAKES_PRIORITY:
+        return priority_[PENDING_TREE];
+      case SAME_PRIORITY_FOR_BOTH_TREES:
+        return combined_priority();
+      default:
+        NOTREACHED();
+        return TilePriority();
+    }
+  }
+
+  TilePriority combined_priority() const {
+    return TilePriority(priority_[ACTIVE_TREE],
+                        priority_[PENDING_TREE]);
+  }
+
+  void SetPriority(WhichTree tree, const TilePriority& priority) {
+    priority_[tree] = priority;
+  }
 
   // TODO(vmpstr): Move this to the iterators.
-  void set_is_occluded(bool is_occluded) { is_occluded_ = is_occluded; }
-  bool is_occluded() const { return is_occluded_; }
+  void set_is_occluded(WhichTree tree, bool is_occluded) {
+    is_occluded_[tree] = is_occluded;
+  }
+
+  bool is_occluded(WhichTree tree) const { return is_occluded_[tree]; }
+
+  void set_shared(bool is_shared) { is_shared_ = is_shared; }
+  bool is_shared() const { return is_shared_; }
+
+  bool is_occluded_combined() const {
+    return is_occluded_[ACTIVE_TREE] && is_occluded_[PENDING_TREE];
+  }
 
   // TODO(vmpstr): Move this to the iterators.
   bool required_for_activation() const { return required_for_activation_; }
@@ -75,7 +108,7 @@
 
   int source_frame_number() const { return source_frame_number_; }
 
-  void set_raster_source(RasterSource* raster_source) {
+  void set_raster_source(scoped_refptr<RasterSource> raster_source) {
     DCHECK(raster_source->CoversRect(content_rect_, contents_scale_))
         << "Recording rect: "
         << gfx::ScaleToEnclosingRect(content_rect_, 1.f / contents_scale_)
@@ -118,9 +151,9 @@
   gfx::Size desired_texture_size_;
   gfx::Rect content_rect_;
   float contents_scale_;
-  bool is_occluded_;
+  bool is_occluded_[LAST_TREE + 1];
 
-  TilePriority priority_;
+  TilePriority priority_[LAST_TREE + 1];
   TileDrawInfo draw_info_;
 
   int layer_id_;
@@ -128,6 +161,7 @@
   int flags_;
   int tiling_i_index_;
   int tiling_j_index_;
+  bool is_shared_ : 1;
   bool required_for_activation_ : 1;
   bool required_for_draw_ : 1;