Simplify platform_canvas.h by recognizing that PlatformCanvas does not actually extend

chrome/renderer/chrome_render_view_observer.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.
 
 #include "chrome/renderer/chrome_render_view_observer.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 132 matching lines @@
   INSECURE_CONTENT_DISPLAY_HOST_GOOGLE_SUPPORT,
   INSECURE_CONTENT_RUN_HOST_GOOGLE_SUPPORT,
   INSECURE_CONTENT_DISPLAY_HOST_GOOGLE_INTL,
   INSECURE_CONTENT_RUN_HOST_GOOGLE_INTL,
   INSECURE_CONTENT_NUM_EVENTS
 };
 
 // Constants for mixed-content blocking.
 static const char kGoogleDotCom[] = "google.com";
 
-static bool PaintViewIntoCanvas(WebView* view,
-                                skia::PlatformCanvas& canvas) {
-  view->layout();
-  const WebSize& size = view->size();
-
-  if (!canvas.initialize(size.width, size.height, true))
-    return false;
-
-  view->paint(webkit_glue::ToWebCanvas(&canvas),
-              WebRect(0, 0, size.width, size.height));
-  // TODO: Add a way to snapshot the whole page, not just the currently
-  // visible part.
-
-  return true;
-}
-
 static FaviconURL::IconType ToFaviconType(WebIconURL::Type type) {
   switch (type) {
     case WebIconURL::TypeFavicon:
       return FaviconURL::FAVICON;
     case WebIconURL::TypeTouch:
       return FaviconURL::TOUCH_ICON;
     case WebIconURL::TypeTouchPrecomposed:
       return FaviconURL::TOUCH_PRECOMPOSED_ICON;
     case WebIconURL::TypeInvalid:
       return FaviconURL::INVALID_ICON;
@@ skipping 718 matching lines @@
     if (last_space_index == std::wstring::npos)
       return;  // don't index if we got a huge block of text with no spaces
     contents->resize(last_space_index);
   }
 }
 
 bool ChromeRenderViewObserver::CaptureSnapshot(WebView* view,
                                                SkBitmap* snapshot) {
   base::TimeTicks beginning_time = base::TimeTicks::Now();
 
-  skia::PlatformCanvas canvas;
-  if (!PaintViewIntoCanvas(view, canvas))
+  view->layout();
+  const WebSize& size = view->size();
+
+  SkCanvas* canvas = skia::CreatePlatformCanvas(size.width, size.height, true,
+                                            NULL, skia::RETURN_NULL_ON_FAILURE);
+  if (!canvas)
     return false;
 
-  SkDevice* device = skia::GetTopDevice(canvas);
+  SkAutoUnref au(canvas);
+  view->paint(webkit_glue::ToWebCanvas(canvas),
+              WebRect(0, 0, size.width, size.height));
+  // TODO: Add a way to snapshot the whole page, not just the currently
+  // visible part.
+
+  SkDevice* device = skia::GetTopDevice(*canvas);
 
   const SkBitmap& bitmap = device->accessBitmap(false);
   if (!bitmap.copyTo(snapshot, SkBitmap::kARGB_8888_Config))
     return false;
 
   HISTOGRAM_TIMES("Renderer4.Snapshot",
                   base::TimeTicks::Now() - beginning_time);
   return true;
 }
 
@@ skipping 56 matching lines @@
         reinterpret_cast<const unsigned char*>(&data[0]);
 
     return decoder.Decode(src_data, data.size());
   }
   return SkBitmap();
 }
 
 bool ChromeRenderViewObserver::IsStrictSecurityHost(const std::string& host) {
   return (strict_security_hosts_.find(host) != strict_security_hosts_.end());
 }