Mark children of an SVG root as needing paint invalidation checking on resize.

third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp

Index: third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp
diff --git a/third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp b/third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp
index 285aa44af64a71b6c83b90ad5e4e66531e9676bc..beee92bad6166c27a3e5236d8fcaa7b40bf888e1 100644
--- a/third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp
+++ b/third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp
@@ -155,6 +155,11 @@ void LayoutSVGRoot::layout() {
   m_isLayoutSizeChanged =
       svg->hasRelativeLengths() && (selfNeedsLayout() || oldSize != size());
 
+  // The scale of one or more of the SVG elements may have changed, so mark
+  // the entire subtree as needing paint invalidation checking.
+  if (m_isLayoutSizeChanged)
+    setMayNeedPaintInvalidationSubtree();
+
   SVGLayoutSupport::layoutChildren(
       firstChild(), false, m_didScreenScaleFactorChange, m_isLayoutSizeChanged);