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 d378a90350af0e8fafaa7481c7084798e54ac654..070ce8d555877267066f0b13dcfea3ce6f474a08 100644
--- a/third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp
+++ b/third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp
@@ -157,6 +157,11 @@ void LayoutSVGRoot::layout()
     // (hence no one is interested in viewport size changes).
     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);
 
     if (m_needsBoundariesOrTransformUpdate) {