First fix to minimize copying of image data.

app/theme_provider.h

Index: app/theme_provider.h
diff --git a/app/theme_provider.h b/app/theme_provider.h
index c3b8a9c26eb87c3d9d8d1bb69f3acde55e46a35b..410e69976bcb24e42375f85cf4628d0e13e72172 100644
--- a/app/theme_provider.h
+++ b/app/theme_provider.h
@@ -23,6 +23,7 @@ class NSImage;
 #endif  // OS_*
 
 class Profile;
+class RefCountedMemory;
 class SkBitmap;
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -60,10 +61,9 @@ class ThemeProvider {
   // doesn't provide a certain image, but custom themes might (badges, etc).
   virtual bool HasCustomImage(int id) const = 0;
 
-  // Reads the image data from the theme file into the specified vector. Returns
-  // true on success.
-  virtual bool GetRawData(int id,
-                          std::vector<unsigned char>* raw_data) const = 0;
+  // Reads the image data from the theme file into the specified
+  // vector. Returns NULL on error.
+  virtual RefCountedMemory* GetRawData(int id) const = 0;
 
 #if defined(OS_LINUX) && !defined(TOOLKIT_VIEWS)
   // Gets the GdkPixbuf with the specified |id|.  Returns a pointer to a shared