cc: Moving anti-aliasing decision to parent compositor.

cc/draw_quad.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_DRAW_QUAD_H_
 #define CC_DRAW_QUAD_H_
 
 #include "base/callback.h"
 #include "cc/cc_export.h"
 #include "cc/resource_provider.h"
@@ skipping 49 matching lines @@
   // With this setting, it is possible to force blending on regardless of the
   // opaque area.
   bool needs_blending;
 
   // Stores state common to a large bundle of quads; kept separate for memory
   // efficiency. There is special treatment to reconstruct these pointers
   // during serialization.
   const SharedQuadState* shared_quad_state;
 
   bool IsDebugQuad() const { return material == DEBUG_BORDER; }
+
   bool ShouldDrawWithBlending() const {
     return needs_blending || shared_quad_state->opacity < 1.0f ||
         !opaque_rect.Contains(visible_rect);
   }
 
   typedef base::Callback<ResourceProvider::ResourceId(
       ResourceProvider::ResourceId)> ResourceIteratorCallback;
   virtual void IterateResources(const ResourceIteratorCallback& callback) = 0;
 
+  // Is the left edge of this tile aligned with the originating layer's
+  // left edge?
+  bool IsLeftEdge() const { return !rect.x(); }
+
+  // Is the top edge of this tile aligned with the originating layer's
+  // top edge?
+  bool IsTopEdge() const { return !rect.y(); }
+
+  // Is the right edge of this tile aligned with the originating layer's
+  // right edge?
+  bool IsRightEdge() const {
+    return rect.right() == shared_quad_state->content_bounds.width();
+  }
+
+  // Is the bottom edge of this tile aligned with the originating layer's
+  // bottom edge?
+  bool IsBottomEdge() const {
+    return rect.bottom() == shared_quad_state->content_bounds.height();
+  }
+
+  // Is any edge of this tile aligned with the originating layer's
+  // corresponding edge?
+  bool IsEdge() const {
+    return IsLeftEdge() || IsTopEdge() || IsRightEdge() || IsBottomEdge();
+  }
+
  protected:
   DrawQuad();
 
   void SetAll(const SharedQuadState* shared_quad_state,
               Material material,
               gfx::Rect rect,
               gfx::Rect opaque_rect,
               gfx::Rect visible_rect,
               bool needs_blending);
 };
 
 }
 
 #endif  // CC_DRAW_QUAD_H_