Make CSSStyleImageValue a member of CanvasImageSource.

third_party/WebKit/Source/modules/canvas2d/BaseRenderingContext2D.cpp

Index: third_party/WebKit/Source/modules/canvas2d/BaseRenderingContext2D.cpp
diff --git a/third_party/WebKit/Source/modules/canvas2d/BaseRenderingContext2D.cpp b/third_party/WebKit/Source/modules/canvas2d/BaseRenderingContext2D.cpp
index ba022bd5e935d384778aa0a7db30851442ef4389..3931b164437a4d37e92317a49c7d1391b0749d90 100644
--- a/third_party/WebKit/Source/modules/canvas2d/BaseRenderingContext2D.cpp
+++ b/third_party/WebKit/Source/modules/canvas2d/BaseRenderingContext2D.cpp
@@ -7,6 +7,7 @@
 #include "bindings/core/v8/ExceptionMessages.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
+#include "core/css/cssom/CSSURLImageValue.h"
 #include "core/css/parser/CSSParser.h"
 #include "core/frame/ImageBitmap.h"
 #include "core/html/HTMLCanvasElement.h"
@@ -865,6 +866,8 @@ static inline void clipRectsToImageRect(const FloatRect& imageRect, FloatRect* s
 
 static inline CanvasImageSource* toImageSourceInternal(const CanvasImageSourceUnion& value, ExceptionState& exceptionState)
 {
+    if (value.isCSSImageValue())

[ikilpatrick, 2016/09/27 18:06:00]

it might be worth making this conditional on CSSPaintAPI as well at the moment,
but see what junov thinks.

[Gleb Lanbin, 2016/09/28 16:58:22]

Done.

+        return value.getAsCSSImageValue();
     if (value.isHTMLImageElement())
         return value.getAsHTMLImageElement();
     if (value.isHTMLVideoElement())