Avoid calling imageForCurrentFrame needlessly on SVGImageForContainer

Propagate SVGImage::isTextureBacked() through SVGImageForContainer to
make https://codereview.chromium.org/1438663002 effective in more
cases.

BUG=552406

Review URL: https://codereview.chromium.org/1635123002

Cr-Commit-Position: refs/heads/master@{#371535}

third_party/WebKit/Source/core/svg/graphics/SVGImageForContainer.cpp

@@ -27,6 +27,11 @@
 
 namespace blink {
 
+bool SVGImageForContainer::isTextureBacked()
+{
+    return m_image->isTextureBacked();
+}
+
 IntSize SVGImageForContainer::size() const
 {
     FloatSize scaledContainerSize(m_containerSize);

third_party/WebKit/Source/core/svg/graphics/SVGImageForContainer.h

@@ -44,6 +44,7 @@ public:
         return adoptRef(new SVGImageForContainer(image, containerSizeWithoutZoom, zoom, url));
     }
 
+    bool isTextureBacked() override;
     IntSize size() const override;
 
     bool usesContainerSize() const override { return m_image->usesContainerSize(); }