Allow fallbackFactory to be null in RecordingImageBufferSurface.

third_party/WebKit/Source/platform/graphics/RecordingImageBufferSurface.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/graphics/RecordingImageBufferSurface.h"
 
 #include "platform/Histogram.h"
 #include "platform/graphics/CanvasMetrics.h"
 #include "platform/graphics/ExpensiveCanvasHeuristicParameters.h"
 #include "platform/graphics/GraphicsContext.h"
@@ skipping 52 matching lines @@
         if (x <= 0 && y <= 0 && x + origInfo.width() >= size().width() && y + origInfo.height() >= size().height()) {
             willOverwriteCanvas();
         }
         fallBackToRasterCanvas(FallbackReasonWritePixels);
     }
     return m_fallbackSurface->writePixels(origInfo, pixels, rowBytes, x, y);
 }
 
 void RecordingImageBufferSurface::fallBackToRasterCanvas(FallbackReason reason)
 {
+    ASSERT(m_fallbackFactory);
+
     if (m_fallbackSurface) {
         ASSERT(!m_currentFrame);
         return;
     }
 
     DEFINE_THREAD_SAFE_STATIC_LOCAL(EnumerationHistogram, canvasFallbackHistogram, new EnumerationHistogram("Canvas.DisplayListFallbackReason", FallbackReasonCount));
     canvasFallbackHistogram.count(reason);
 
     m_fallbackSurface = m_fallbackFactory->createSurface(size(), getOpacityMode());
     m_fallbackSurface->setImageBuffer(m_imageBuffer);
@@ skipping 88 matching lines @@
 
 PassRefPtr<SkPicture> RecordingImageBufferSurface::getPicture()
 {
     if (m_fallbackSurface)
         return nullptr;
 
     FallbackReason fallbackReason = FallbackReasonUnknown;
     bool canUsePicture = finalizeFrameInternal(&fallbackReason);
     m_imageBuffer->didFinalizeFrame();
 
+    ASSERT(canUsePicture || m_fallbackFactory);
+
     if (canUsePicture) {
         return m_previousFrame;
     }
 
     if (!m_fallbackSurface)
         fallBackToRasterCanvas(fallbackReason);
     return nullptr;
 }
 
 void RecordingImageBufferSurface::finalizeFrame(const FloatRect &dirtyRect)
@@ skipping 64 matching lines @@
             initializeCurrentFrame();
         }
         return m_currentFrame.get();
     }
 
     if (!m_frameWasCleared) {
         *fallbackReason = FallbackReasonCanvasNotClearedBetweenFrames;
         return false;
     }
 
-    if (m_currentFrame->getRecordingCanvas()->getSaveCount() > ExpensiveCanvasHeuristicParameters::ExpensiveRecordingStackDepth) {
+    if (m_fallbackFactory && m_currentFrame->getRecordingCanvas()->getSaveCount() > ExpensiveCanvasHeuristicParameters::ExpensiveRecordingStackDepth) {
         *fallbackReason = FallbackReasonRunawayStateStack;
         return false;
     }
 
     m_previousFrame = fromSkSp(m_currentFrame->finishRecordingAsPicture());
     m_previousFrameHasExpensiveOp = m_currentFrameHasExpensiveOp;
     m_previousFramePixelCount = m_currentFramePixelCount;
     initializeCurrentFrame();
 
     m_frameWasCleared = false;
@@ skipping 67 matching lines @@
 
 void RecordingImageBufferSurface::setIsHidden(bool hidden)
 {
     if (m_fallbackSurface)
         m_fallbackSurface->setIsHidden(hidden);
     else
         ImageBufferSurface::setIsHidden(hidden);
 }
 
 } // namespace blink