Add Image::updateConcreteSize()

third_party/WebKit/Source/platform/graphics/Image.h

Index: third_party/WebKit/Source/platform/graphics/Image.h
diff --git a/third_party/WebKit/Source/platform/graphics/Image.h b/third_party/WebKit/Source/platform/graphics/Image.h
index 089832c197e5a14e75ae4d74942c02ab48900297..ae90da00a6ed04bf1ac93a224b8ae5be302017c3 100644
--- a/third_party/WebKit/Source/platform/graphics/Image.h
+++ b/third_party/WebKit/Source/platform/graphics/Image.h
@@ -98,6 +98,16 @@ public:
     // images it can be the dimensions defined by the 'viewBox'.)
     virtual void computeIntrinsicDimensions(FloatSize& intrinsicSize, FloatSize& intrinsicRatio);
 
+    // "The concrete object size is the result of combining an
+    // object's intrinsic dimensions and specified size with the
+    // default object size of the context it’s used in, producing a
+    // rectangle with a definite width and height."
+    //
+    // https://drafts.csswg.org/css-images-3/#concrete-object-size
+    //
+    // Updates the image size to a new default object size.
+    virtual void updateConcreteObjectSize(const LayoutSize& defaultObjectSize) {}
+
     virtual IntSize size() const = 0;
     IntRect rect() const { return IntRect(IntPoint(), size()); }
     int width() const { return size().width(); }