Change Canvas2DLayerBridge to stay alive until last mailbox is returned.

Source/core/platform/graphics/ImageBuffer.cpp

 /*
  * Copyright (c) 2008, Google Inc. All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
@@ skipping 43 matching lines @@
 #include "third_party/skia/include/gpu/GrContext.h"
 #include "third_party/skia/include/gpu/SkGpuDevice.h"
 #include "wtf/MathExtras.h"
 #include "wtf/text/Base64.h"
 #include "wtf/text/WTFString.h"
 
 using namespace std;
 
 namespace WebCore {
 
-static SkCanvas* createAcceleratedCanvas(const IntSize& size, OwnPtr<Canvas2DLayerBridge>* outLayerBridge, OpacityMode opacityMode)
+static SkCanvas* createAcceleratedCanvas(const IntSize& size, Canvas2DLayerBridgePtr* outLayerBridge, OpacityMode opacityMode)
 {
     RefPtr<GraphicsContext3D> context3D = SharedGraphicsContext3D::get();
     if (!context3D)
         return 0;
     Canvas2DLayerBridge::OpacityMode bridgeOpacityMode = opacityMode == Opaque ? Canvas2DLayerBridge::Opaque : Canvas2DLayerBridge::NonOpaque;
     *outLayerBridge = Canvas2DLayerBridge::create(context3D.release(), size, bridgeOpacityMode);
     // If canvas buffer allocation failed, debug build will have asserted
     // For release builds, we must verify whether the device has a render target
-    return (*outLayerBridge) ? (*outLayerBridge)->getCanvas() : 0;
+    return outLayerBridge->get() ? (*outLayerBridge)->getCanvas() : 0;
 }
 
 static SkCanvas* createNonPlatformCanvas(const IntSize& size)
 {
     SkAutoTUnref<SkDevice> device(new SkDevice(SkBitmap::kARGB_8888_Config, size.width(), size.height()));
     SkPixelRef* pixelRef = device->accessBitmap(false).pixelRef();
     return pixelRef ? new SkCanvas(device) : 0;
 }
 
 PassOwnPtr<ImageBuffer> ImageBuffer::createCompatibleBuffer(const IntSize& size, float resolutionScale, const GraphicsContext* context, bool hasAlpha)
@@ skipping 72 matching lines @@
 
     success = true;
 }
 
 ImageBuffer::~ImageBuffer()
 {
 }
 
 GraphicsContext* ImageBuffer::context() const
 {
-    if (m_layerBridge) {
+    if (m_layerBridge.get()) {
         // We're using context acquisition as a signal that someone is about to render into our buffer and we need
         // to be ready. This isn't logically const-correct, hence the cast.
         const_cast<Canvas2DLayerBridge*>(m_layerBridge.get())->contextAcquired();
     }
     return m_context.get();
 }
 
 
 bool ImageBuffer::isValid() const
 {
@@ skipping 21 matching lines @@
     return BitmapImage::create(NativeImageSkia::create(copyBehavior == CopyBackingStore ? deepSkBitmapCopy(bitmap) : bitmap, m_resolutionScale));
 }
 
 BackingStoreCopy ImageBuffer::fastCopyImageMode()
 {
     return DontCopyBackingStore;
 }
 
 WebKit::WebLayer* ImageBuffer::platformLayer() const
 {
-    return m_layerBridge ? m_layerBridge->layer() : 0;
+    return m_layerBridge.get() ? m_layerBridge->layer() : 0;
 }
 
 bool ImageBuffer::copyToPlatformTexture(GraphicsContext3D& context, Platform3DObject texture, GC3Denum internalFormat, GC3Denum destType, GC3Dint level, bool premultiplyAlpha, bool flipY)
 {
-    if (!m_layerBridge || !platformLayer() || !isValid())
+    if (!m_layerBridge.get() || !platformLayer() || !isValid())
         return false;
 
     Platform3DObject sourceTexture = m_layerBridge->backBufferTexture();
 
     if (!context.makeContextCurrent())
         return false;
 
     Extensions3D* extensions = context.getExtensions();
     if (!extensions->supports("GL_CHROMIUM_copy_texture") || !extensions->supports("GL_CHROMIUM_flipy")
         || !extensions->canUseCopyTextureCHROMIUM(internalFormat, destType, level))
@@ skipping 265 matching lines @@
     if (!encodeImage(imageData, mimeType, quality, &encodedImage))
         return "data:,";
 
     Vector<char> base64Data;
     base64Encode(encodedImage, base64Data);
 
     return "data:" + mimeType + ";base64," + base64Data;
 }
 
 } // namespace WebCore