Add "premultiply" in ImageBitmapOptions enum PremultiplyAlpha

third_party/WebKit/Source/core/frame/ImageBitmap.cpp

 // Copyright 2013 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 "core/frame/ImageBitmap.h"
 
 #include "core/html/HTMLCanvasElement.h"
 #include "core/html/HTMLVideoElement.h"
 #include "core/html/ImageData.h"
 #include "platform/image-decoders/ImageDecoder.h"
@@ skipping 411 matching lines @@
 {
     if (options.imageOrientation() == imageOrientationFlipY) {
         flipY = true;
     } else {
         flipY = false;
         ASSERT(options.imageOrientation() == imageBitmapOptionNone);
     }
     if (options.premultiplyAlpha() == imageBitmapOptionNone) {
         m_isPremultiplied = false;
     } else {
-        ASSERT(options.premultiplyAlpha() == "default");
+        ASSERT(options.premultiplyAlpha() == "default" || options.premultiplyAlpha() == "premultiply");
     }
 }
 
 PassRefPtr<Image> ImageBitmap::getSourceImageForCanvas(SourceImageStatus* status, AccelerationHint, SnapshotReason) const
 {
     *status = NormalSourceImageStatus;
     return m_image ? m_image : nullptr;
 }
 
 void ImageBitmap::adjustDrawRects(FloatRect* srcRect, FloatRect* dstRect) const
 {
 }
 
 FloatSize ImageBitmap::elementSize() const
 {
     return FloatSize(width(), height());
 }
 
 DEFINE_TRACE(ImageBitmap)
 {
 }
 
 } // namespace blink