Deal gracefully with null {GraphicsContext,SkPictureBuilder}.endRecording() results.

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

 /*
  * Copyright (C) 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  * Copyright 2014 The Chromium Authors. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 91 matching lines @@
         if (attributes.viewBox().isEmpty())
             return nullptr;
         tileTransform = SVGFitToViewBox::viewBoxToViewTransform(attributes.viewBox(),
             attributes.preserveAspectRatio(), tileBounds.width(), tileBounds.height());
     } else {
         // A viewbox overrides patternContentUnits, per spec.
         if (attributes.patternContentUnits() == SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX)
             tileTransform.scale(clientBoundingBox.width(), clientBoundingBox.height());
     }
 
+    RefPtr<SkPicture> recording = asPicture(tileBounds, tileTransform);
+    if (!recording)
+        return nullptr;

[chrishtr, 2016/03/29 22:42:23]

Callsites are robust against this?

[wkorman, 2016/03/29 22:52:02]

Yes.

+
     OwnPtr<PatternData> patternData = adoptPtr(new PatternData);
-    patternData->pattern = Pattern::createPicturePattern(asPicture(tileBounds, tileTransform));
+    patternData->pattern = Pattern::createPicturePattern(recording);
 
     // Compute pattern space transformation.
     patternData->transform.translate(tileBounds.x(), tileBounds.y());
     patternData->transform.preMultiply(attributes.patternTransform());
 
     return patternData.release();
 }
 
 SVGPaintServer LayoutSVGResourcePattern::preparePaintServer(const LayoutObject& object)
 {
@@ skipping 75 matching lines @@
     {
         TransformRecorder transformRecorder(pictureBuilder.context(), *patternLayoutObject, tileTransform);
         for (LayoutObject* child = patternLayoutObject->firstChild(); child; child = child->nextSibling())
             SVGPaintContext::paintSubtree(pictureBuilder.context(), child);
     }
 
     return pictureBuilder.endRecording();
 }
 
 } // namespace blink