Tag TransportDIBs with the device scale factor they expect.

content/browser/renderer_host/backing_store_manager.h

Index: content/browser/renderer_host/backing_store_manager.h
diff --git a/content/browser/renderer_host/backing_store_manager.h b/content/browser/renderer_host/backing_store_manager.h
index 1282e66084253594d6a38656e9f5237a19b7e09e..75d23261267fcbabad5fc7e96d2187cd221c897c 100644
--- a/content/browser/renderer_host/backing_store_manager.h
+++ b/content/browser/renderer_host/backing_store_manager.h
@@ -39,11 +39,17 @@ class BackingStoreManager {
   // bitmap from the renderer has been copied into the backing store.
   //
   // backing_store_size
-  //   The desired backing store dimensions.
+  //   The desired backing store dimensions, in DIPs.
   // bitmap_section
   //   The bitmap section from the renderer.
   // bitmap_rect
-  //   The rect to be painted into the backing store
+  //   The rect to be painted into the backing store, in DIPs.
+  // scale_factor
+  //   The device scale facctor the backing store is expected to be at.

[Avi (use Gerrit), 2012/06/13 20:44:40]

s/facctor/factor/

+  //   If the backing store's device scale factor doesn't match, it will need
+  //   to scale |bitmap| at paint time. This will only be out of sync with the
+  //   backing store scale factor for a few frames, right after device scale
+  //   changes.
   // needs_full_paint
   //   Set if we need to send out a request to paint the view
   //   to the renderer.
@@ -53,6 +59,7 @@ class BackingStoreManager {
       TransportDIB::Id bitmap,
       const gfx::Rect& bitmap_rect,
       const std::vector<gfx::Rect>& copy_rects,
+      float scale_factor,
       const base::Closure& completion_callback,
       bool* needs_full_paint,
       bool* scheduled_completion_callback);