avoid calling host() directly for imageBuffer on 2D rendenring contexts

third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp

 // Copyright 2016 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 "modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.h"
 
 #include "bindings/modules/v8/OffscreenCanvasRenderingContext2DOrWebGLRenderingContextOrWebGL2RenderingContext.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/frame/ImageBitmap.h"
 #include "core/frame/Settings.h"
@@ skipping 92 matching lines @@
 
 ImageBuffer* OffscreenCanvasRenderingContext2D::GetImageBuffer() const {
   return const_cast<CanvasRenderingContextHost*>(host())
       ->GetOrCreateImageBuffer();
 }
 
 RefPtr<StaticBitmapImage>
 OffscreenCanvasRenderingContext2D::TransferToStaticBitmapImage() {
   if (!GetImageBuffer())
     return nullptr;
-  sk_sp<SkImage> sk_image = host()->GetImageBuffer()->NewSkImageSnapshot(
+  sk_sp<SkImage> sk_image = GetImageBuffer()->NewSkImageSnapshot(
       kPreferAcceleration, kSnapshotReasonTransferToImageBitmap);
   RefPtr<StaticBitmapImage> image =
       StaticBitmapImage::Create(std::move(sk_image));
   image->SetOriginClean(this->OriginClean());
   return image;
 }
 
 ImageBitmap* OffscreenCanvasRenderingContext2D::TransferToImageBitmap(
     ScriptState* script_state) {
   UseCounter::Feature feature =
       UseCounter::kOffscreenCanvasTransferToImageBitmap2D;
   UseCounter::Count(ExecutionContext::From(script_state), feature);
   RefPtr<StaticBitmapImage> image = TransferToStaticBitmapImage();
   if (!image)
     return nullptr;
   host()->DiscardImageBuffer();  // "Transfer" means no retained buffer
   return ImageBitmap::Create(std::move(image));
 }
 
 PassRefPtr<Image> OffscreenCanvasRenderingContext2D::GetImage(
     AccelerationHint hint,
     SnapshotReason reason) const {
   if (!GetImageBuffer())
     return nullptr;
-  sk_sp<SkImage> sk_image =
-      host()->GetImageBuffer()->NewSkImageSnapshot(hint, reason);
+  sk_sp<SkImage> sk_image = GetImageBuffer()->NewSkImageSnapshot(hint, reason);
   RefPtr<StaticBitmapImage> image =
       StaticBitmapImage::Create(std::move(sk_image));
   return image;
 }
 
 ImageData* OffscreenCanvasRenderingContext2D::ToImageData(
     SnapshotReason reason) {
   if (!GetImageBuffer())
     return nullptr;
-  sk_sp<SkImage> snapshot = host()->GetImageBuffer()->NewSkImageSnapshot(
-      kPreferNoAcceleration, reason);
+  sk_sp<SkImage> snapshot =
+      GetImageBuffer()->NewSkImageSnapshot(kPreferNoAcceleration, reason);
   ImageData* image_data = nullptr;
   if (snapshot) {
     image_data = ImageData::Create(host()->Size());
     SkImageInfo image_info =
         SkImageInfo::Make(this->Width(), this->Height(), kRGBA_8888_SkColorType,
                           kUnpremul_SkAlphaType);
     snapshot->readPixels(image_info, image_data->data()->Data(),
                          image_info.minRowBytes(), 0, 0);
   }
   return image_data;
@@ skipping 11 matching lines @@
 }
 
 PaintCanvas* OffscreenCanvasRenderingContext2D::DrawingCanvas() const {
   ImageBuffer* buffer = GetImageBuffer();
   if (!buffer)
     return nullptr;
   return GetImageBuffer()->Canvas();
 }
 
 PaintCanvas* OffscreenCanvasRenderingContext2D::ExistingDrawingCanvas() const {
-  if (!host()->GetImageBuffer())
+  if (!HasImageBuffer())
     return nullptr;
-  return host()->GetImageBuffer()->Canvas();
+  return GetImageBuffer()->Canvas();
 }
 
 void OffscreenCanvasRenderingContext2D::DisableDeferral(DisableDeferralReason) {
 }
 
 AffineTransform OffscreenCanvasRenderingContext2D::BaseTransform() const {
-  if (!host()->GetImageBuffer())
+  if (!HasImageBuffer())
     return AffineTransform();  // identity
-  return host()->GetImageBuffer()->BaseTransform();
+  return GetImageBuffer()->BaseTransform();
 }
 
 void OffscreenCanvasRenderingContext2D::DidDraw(const SkIRect& dirty_rect) {}
 
 bool OffscreenCanvasRenderingContext2D::StateHasFilter() {
   return GetState().HasFilterForOffscreenCanvas(host()->Size());
 }
 
 sk_sp<SkImageFilter> OffscreenCanvasRenderingContext2D::StateGetFilter() {
   return GetState().GetFilterForOffscreenCanvas(host()->Size());
@@ skipping 22 matching lines @@
 
 String OffscreenCanvasRenderingContext2D::ColorSpaceAsString() const {
   return CanvasRenderingContext::ColorSpaceAsString();
 }
 
 CanvasPixelFormat OffscreenCanvasRenderingContext2D::PixelFormat() const {
   return color_params().pixel_format();
 }
 
 bool OffscreenCanvasRenderingContext2D::IsAccelerated() const {
-  return host()->GetImageBuffer() && host()->GetImageBuffer()->IsAccelerated();
+  return HasImageBuffer() && GetImageBuffer()->IsAccelerated();
 }
 }