Add "alpha" option to PaintWorklet

third_party/WebKit/Source/modules/csspaint/CSSPaintDefinition.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/csspaint/CSSPaintDefinition.h"
 
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8BindingMacros.h"
 #include "bindings/core/v8/V8ObjectConstructor.h"
 #include "core/css/CSSComputedStyleDeclaration.h"
 #include "core/css/cssom/FilteredComputedStylePropertyMap.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/layout/LayoutObject.h"
 #include "modules/csspaint/PaintRenderingContext2D.h"
 #include "modules/csspaint/PaintSize.h"
 #include "platform/graphics/ImageBuffer.h"
 #include "platform/graphics/PaintGeneratedImage.h"
 #include "platform/graphics/RecordingImageBufferSurface.h"
 #include "wtf/PtrUtil.h"
 
 namespace blink {
 
-CSSPaintDefinition* CSSPaintDefinition::create(ScriptState* scriptState, v8::Local<v8::Function> constructor, v8::Local<v8::Function> paint, Vector<CSSPropertyID>& nativeInvalidationProperties, Vector<AtomicString>& customInvalidationProperties)
+CSSPaintDefinition* CSSPaintDefinition::create(ScriptState* scriptState, v8::Local<v8::Function> constructor, v8::Local<v8::Function> paint, Vector<CSSPropertyID>& nativeInvalidationProperties, Vector<AtomicString>& customInvalidationProperties, bool hasAlphaChannel)
 {
-    return new CSSPaintDefinition(scriptState, constructor, paint, nativeInvalidationProperties, customInvalidationProperties);
+    return new CSSPaintDefinition(scriptState, constructor, paint, nativeInvalidationProperties, customInvalidationProperties, hasAlphaChannel);
 }
 
-CSSPaintDefinition::CSSPaintDefinition(ScriptState* scriptState, v8::Local<v8::Function> constructor, v8::Local<v8::Function> paint, Vector<CSSPropertyID>& nativeInvalidationProperties, Vector<AtomicString>& customInvalidationProperties)
+CSSPaintDefinition::CSSPaintDefinition(ScriptState* scriptState, v8::Local<v8::Function> constructor, v8::Local<v8::Function> paint, Vector<CSSPropertyID>& nativeInvalidationProperties, Vector<AtomicString>& customInvalidationProperties, bool hasAlphaChannel)
     : m_scriptState(scriptState)
     , m_constructor(scriptState->isolate(), constructor)
     , m_paint(scriptState->isolate(), paint)
+    , m_didCallConstructor(false)
+    , m_hasAlphaChannel(hasAlphaChannel)
 {
     m_nativeInvalidationProperties.swap(nativeInvalidationProperties);
     m_customInvalidationProperties.swap(customInvalidationProperties);
 }
 
 CSSPaintDefinition::~CSSPaintDefinition()
 {
 }
 
 PassRefPtr<Image> CSSPaintDefinition::paint(const LayoutObject& layoutObject, const IntSize& size)
 {
     ScriptState::Scope scope(m_scriptState.get());
 
     maybeCreatePaintInstance();
 
     v8::Isolate* isolate = m_scriptState->isolate();
     v8::Local<v8::Object> instance = m_instance.newLocal(isolate);
 
     // We may have failed to create an instance class, in which case produce an
     // invalid image.
     if (isUndefinedOrNull(instance))
         return nullptr;
 
     DCHECK(layoutObject.node());
 
     PaintRenderingContext2D* renderingContext = PaintRenderingContext2D::create(
-        ImageBuffer::create(wrapUnique(new RecordingImageBufferSurface(size))));
+        ImageBuffer::create(wrapUnique(new RecordingImageBufferSurface(size, nullptr /* fallbackFactory */, m_hasAlphaChannel ? NonOpaque : Opaque))),  m_hasAlphaChannel);
     PaintSize* paintSize = PaintSize::create(size);
     StylePropertyMap* styleMap = FilteredComputedStylePropertyMap::create(
         CSSComputedStyleDeclaration::create(layoutObject.node()),
         m_nativeInvalidationProperties, m_customInvalidationProperties);
 
     v8::Local<v8::Value> argv[] = {
         toV8(renderingContext, m_scriptState->context()->Global(), isolate),
         toV8(paintSize, m_scriptState->context()->Global(), isolate),
         toV8(styleMap, m_scriptState->context()->Global(), isolate)
     };
@@ skipping 27 matching lines @@
 
     v8::Local<v8::Object> paintInstance;
     if (V8ObjectConstructor::newInstance(isolate, constructor).ToLocal(&paintInstance)) {
         m_instance.set(isolate, paintInstance);
     }
 
     m_didCallConstructor = true;
 }
 
 } // namespace blink