No need to kClear_Mode a layer right after its created, as that will automatically

chrome/browser/download/download_util.cc

 // Copyright (c) 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.
 //
 // Download utility implementation
 
 #define _USE_MATH_DEFINES  // For VC++ to get M_PI. This has to be first.
 
 #include "chrome/browser/download/download_util.h"
 
@@ skipping 252 matching lines @@
 
   gfx::Rect complete_bounds(origin_x, origin_y,
                             complete->width(), complete->height());
 #if defined(TOOLKIT_VIEWS)
   // Mirror the positions if necessary.
   complete_bounds.set_x(containing_view->GetMirroredXForRect(complete_bounds));
 #endif
 
   // Start at full opacity, then loop back and forth five times before ending
   // at zero opacity.
-  canvas->SaveLayerAlpha(GetOpacity(animation_progress), complete_bounds);
-  canvas->sk_canvas()->drawARGB(0, 255, 255, 255, SkXfermode::kClear_Mode);
-  canvas->DrawImageInt(*complete, complete_bounds.x(), complete_bounds.y());
-  canvas->Restore();
+  canvas->DrawImageInt(*complete, complete_bounds.x(), complete_bounds.y(),
+                       GetOpacity(animation_progress));
 }
 
 void PaintDownloadInterrupted(gfx::Canvas* canvas,
 #if defined(TOOLKIT_VIEWS)
                               views::View* containing_view,
 #endif
                               int origin_x,
                               int origin_y,
                               double animation_progress,
                               PaintDownloadProgressSize size) {
   // Load up our common images.
   if (!g_foreground_16) {
     ResourceBundle& rb = ResourceBundle::GetSharedInstance();
     g_foreground_16 = rb.GetImageSkiaNamed(IDR_DOWNLOAD_PROGRESS_FOREGROUND_16);
     g_foreground_32 = rb.GetImageSkiaNamed(IDR_DOWNLOAD_PROGRESS_FOREGROUND_32);
   }
 
   gfx::ImageSkia* complete = (size == BIG) ? g_foreground_32 : g_foreground_16;
 
   gfx::Rect complete_bounds(origin_x, origin_y,
                             complete->width(), complete->height());
 #if defined(TOOLKIT_VIEWS)
   // Mirror the positions if necessary.
   complete_bounds.set_x(containing_view->GetMirroredXForRect(complete_bounds));
 #endif
 
   // Start at zero opacity, then loop back and forth five times before ending
   // at full opacity.
-  canvas->SaveLayerAlpha(GetOpacity(1.0 - animation_progress), complete_bounds);
-  canvas->sk_canvas()->drawARGB(0, 255, 255, 255, SkXfermode::kClear_Mode);
-  canvas->DrawImageInt(*complete, complete_bounds.x(), complete_bounds.y());
-  canvas->Restore();
+  canvas->DrawImageInt(*complete, complete_bounds.x(), complete_bounds.y(),
+                       GetOpacity(1.0 - animation_progress));
 }
 
 // Load a language dependent height so that the dangerous download confirmation
 // message doesn't overlap with the download link label.
 int GetBigProgressIconSize() {
   static int big_progress_icon_size = 0;
   if (big_progress_icon_size == 0) {
     string16 locale_size_str =
         l10n_util::GetStringUTF16(IDS_DOWNLOAD_BIG_PROGRESS_SIZE);
     bool rc = base::StringToInt(locale_size_str, &big_progress_icon_size);
@@ skipping 159 matching lines @@
   UMA_HISTOGRAM_ENUMERATION(
       "Download.CountsChrome", type, CHROME_DOWNLOAD_COUNT_TYPES_LAST_ENTRY);
 }
 
 void RecordDownloadSource(ChromeDownloadSource source) {
   UMA_HISTOGRAM_ENUMERATION(
       "Download.SourcesChrome", source, CHROME_DOWNLOAD_SOURCE_LAST_ENTRY);
 }
 
 }  // namespace download_util