Optionally clear PlatformCanvas instances.

skia/ext/platform_canvas.cc

 // Copyright (c) 2011 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 "skia/ext/platform_canvas.h"
 
 #include "skia/ext/bitmap_platform_device.h"
 #include "third_party/skia/include/core/SkTypes.h"
 
 namespace skia {
@@ skipping 13 matching lines @@
 bool PlatformCanvas::initializeWithDevice(SkDevice* device) {
   if (!device)
     return false;
 
   setDevice(device);
   device->unref();  // Was created with refcount 1, and setDevice also refs.
   return true;
 }
 
 SkCanvas* CreateBitmapCanvas(int width, int height, bool is_opaque) {
-  return new PlatformCanvas(width, height, is_opaque);
+  return CreateBitmapCanvas(width, height,
+                            PlatformDevice::GetDefaultFlags(is_opaque));
+}
+
+SkCanvas* CreateBitmapCanvas(int width, int height, int flags) {
+  return new PlatformCanvas(width, height, flags);
 }
 
 SkCanvas* TryCreateBitmapCanvas(int width, int height, bool is_opaque) {
+  return TryCreateBitmapCanvas(width, height,
+                               PlatformDevice::GetDefaultFlags(is_opaque));
+}
+
+SkCanvas* TryCreateBitmapCanvas(int width, int height, int flags) {
   PlatformCanvas* canvas = new PlatformCanvas();
-  if (!canvas->initialize(width, height, is_opaque)) {
+  if (!canvas->initialize(width, height, flags)) {
     delete canvas;
     canvas = NULL;
   }
   return canvas;
 }
 
 SkDevice* GetTopDevice(const SkCanvas& canvas) {
   SkCanvas::LayerIter iter(const_cast<SkCanvas*>(&canvas), false);
   return iter.device();
 }
@@ skipping 39 matching lines @@
                SkIntToScalar(width), SkIntToScalar(height));
   SkPaint paint;
   // so we don't draw anything on a device that ignores xfermodes
   paint.setColor(0);
   // install our custom mode
   paint.setXfermode(new SkProcXfermode(MakeOpaqueXfermodeProc))->unref();
   canvas->drawRect(rect, paint);
 }
 
 }  // namespace skia