Make CSSValuePool thread local to ensure correct parsing in colors on workers

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/UnionTypesModules.h"
 #include "core/frame/ImageBitmap.h"
 #include "platform/graphics/ImageBuffer.h"
 #include "platform/graphics/StaticBitmapImage.h"
 #include "wtf/Assertions.h"
 
 #define UNIMPLEMENTED ASSERT_NOT_REACHED
 
 namespace blink {
 
 OffscreenCanvasRenderingContext2D::~OffscreenCanvasRenderingContext2D()
 {
 }
 
 OffscreenCanvasRenderingContext2D::OffscreenCanvasRenderingContext2D(OffscreenCanvas* canvas, const CanvasContextCreationAttributes& attrs)
     : OffscreenCanvasRenderingContext(canvas)
     , m_hasAlpha(attrs.alpha())
 {
 }
 
 DEFINE_TRACE(OffscreenCanvasRenderingContext2D)
 {
+    visitor->trace(m_executionContext);
     OffscreenCanvasRenderingContext::trace(visitor);
     BaseRenderingContext2D::trace(visitor);
 }
 
 // BaseRenderingContext2D implementation
 bool OffscreenCanvasRenderingContext2D::originClean() const
 {
     return m_originClean;
 }
 
@@ skipping 41 matching lines @@
         return nullptr;
     // TODO: crbug.com/593514 Add support for GPU rendering
     RefPtr<SkImage> skImage = m_imageBuffer->newSkImageSnapshot(PreferNoAcceleration, SnapshotReasonUnknown);
     RefPtr<StaticBitmapImage> image = StaticBitmapImage::create(skImage.release());
     m_imageBuffer.clear(); // "Transfer" means no retained buffer
     return ImageBitmap::create(image.release());
 }
 
 bool OffscreenCanvasRenderingContext2D::parseColorOrCurrentColor(Color& color, const String& colorString) const
 {
+    if (!m_executionContext)
+        const_cast<OffscreenCanvasRenderingContext2D*>(this)->m_executionContext = ScriptState::current(v8::Isolate::GetCurrent())->getExecutionContext();
+
+    DCHECK(m_executionContext);
+    if (m_executionContext->isWorkerGlobalScope()) {
+        return ::blink::parseColorOrCurrentColor(color, colorString, nullptr, m_executionContext->localCssValuePool());
+    }
+
     return ::blink::parseColorOrCurrentColor(color, colorString, nullptr);
 }
 
 SkCanvas* OffscreenCanvasRenderingContext2D::drawingCanvas() const
 {
     ImageBuffer* buffer = imageBuffer();
     if (!buffer)
         return nullptr;
     return imageBuffer()->canvas();
 }
@@ skipping 41 matching lines @@
     }
 #endif
 }
 
 bool OffscreenCanvasRenderingContext2D::isContextLost() const
 {
     return false;
 }
 
 }