change backing store cache to be memory-based rather than count

chrome/browser/renderer_host/backing_store_x.cc

 // Copyright (c) 2006-2008 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.
 
 #include "chrome/browser/renderer_host/backing_store.h"
 
 #include <stdlib.h>
 #include <utility>
 
 #include "base/compiler_specific.h"
@@ skipping 59 matching lines @@
 BackingStore::~BackingStore() {
   // In unit tests, display_ may be NULL.
   if (!display_)
     return;
 
   XRenderFreePicture(display_, picture_);
   XFreePixmap(display_, pixmap_);
   XFreeGC(display_, static_cast<GC>(pixmap_gc_));
 }
 
+size_t BackingStore::MemorySize() {
+  if (use_render_)

[agl, 2009/06/24 18:53:01]

!use_render_

+    return size_.GetArea() * (pixmap_bpp_ / 8);
+  else
+    return size_.GetArea() * 4;  // TODO(port) is this correct?

[agl, 2009/06/24 18:53:01]

Yes it is, remove TODO

+}
+
 void BackingStore::PaintRectWithoutXrender(TransportDIB* bitmap,
                                            const gfx::Rect &bitmap_rect) {
   const int width = bitmap_rect.width();
   const int height = bitmap_rect.height();
   Pixmap pixmap = XCreatePixmap(display_, root_window_, width, height,
                                 visual_depth_);
 
   XImage image;
   memset(&image, 0, sizeof(image));
 
@@ skipping 244 matching lines @@
 
   bitmap.setConfig(SkBitmap::kARGB_8888_Config, width, height);
   bitmap.allocPixels();
   unsigned char* bitmap_data =
     reinterpret_cast<unsigned char*>(bitmap.getAddr32(0, 0));
   memcpy(bitmap_data, image->data, width * height * kBytesPerPixel);
 
   XFree(image);
   return bitmap;
 }