adding preabandon flag to DM

src/gpu/SkGpuDevice.h

 
 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkGpuDevice_DEFINED
 #define SkGpuDevice_DEFINED
@@ skipping 39 matching lines @@
 
     virtual ~SkGpuDevice();
 
     SkGpuDevice* cloneDevice(const SkSurfaceProps& props) {
         SkBaseDevice* dev = this->onCreateCompatibleDevice(CreateInfo(this->imageInfo(),
                                                                       kGeneral_Usage,
                                                                       props.pixelGeometry()));
         return static_cast<SkGpuDevice*>(dev);
     }
 
-    GrContext* context() const { return fRenderTarget->getContext(); }
+    GrContext* context() const { return fContext; }
 
     // set all pixels to 0
     void clearAll();
 
     void replaceRenderTarget(bool shouldRetainContent);
 
     GrRenderTarget* accessRenderTarget() SK_OVERRIDE;
 
     SkImageInfo imageInfo() const SK_OVERRIDE {
         return fRenderTarget ? fRenderTarget->surfacePriv().info() : SkImageInfo::MakeUnknown();
@@ skipping 132 matching lines @@
 
     static SkPicture::AccelData::Key ComputeAccelDataKey();
 
     static GrRenderTarget* CreateRenderTarget(GrContext*, SkSurface::Budgeted, const SkImageInfo&,
                                               int sampleCount);
 
     typedef SkBaseDevice INHERITED;
 };
 
 #endif