Don't propagate bbox for empty <text> to ancestors

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

 /*
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) 2006 Alexander Kellett <lypanov@kde.org>
  * Copyright (C) 2006 Oliver Hunt <ojh16@student.canterbury.ac.nz>
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) Research In Motion Limited 2010-2012. All rights reserved.
  * Copyright (C) 2012 Google Inc.
  *
@@ skipping 479 matching lines @@
 {
     FloatRect paintInvalidationRect = strokeBoundingBox();
     SVGLayoutSupport::intersectPaintInvalidationRectWithResources(this, paintInvalidationRect);
 
     if (const ShadowList* textShadow = style()->textShadow())
         textShadow->adjustRectForShadow(paintInvalidationRect);
 
     return paintInvalidationRect;
 }
 
+bool LayoutSVGText::isObjectBoundingBoxValid() const
+{
+    // If we don't have any line boxes, then consider the bbox invalid.
+    return firstLineBox();
+}
+
 void LayoutSVGText::addChild(LayoutObject* child, LayoutObject* beforeChild)
 {
     LayoutSVGBlock::addChild(child, beforeChild);
 
     SVGResourcesCache::clientWasAddedToTree(child, child->styleRef());
     subtreeChildWasAdded(child);
 }
 
 void LayoutSVGText::removeChild(LayoutObject* child)
 {
@@ skipping 20 matching lines @@
         paintInvalidationState.pushDelayedPaintInvalidationTarget(*this);
 
     ForceHorriblySlowRectMapping slowRectMapping(&paintInvalidationState);
     PaintInvalidationState childTreeWalkState(paintInvalidationState, *this, paintInvalidationState.paintInvalidationContainer());
     if (reason == PaintInvalidationSVGResourceChange)
         childTreeWalkState.setForceSubtreeInvalidationWithinContainer();
     invalidatePaintOfSubtreesIfNeeded(childTreeWalkState);
 }
 
 } // namespace blink