Shot in the dark to fix 581472

src/gpu/GrDrawingManager.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrDrawContext.h"
 #include "GrDrawingManager.h"
 #include "GrDrawTarget.h"
@@ skipping 49 matching lines @@
 }
 
 void GrDrawingManager::reset() {
     for (int i = 0; i < fDrawTargets.count(); ++i) {
         fDrawTargets[i]->reset();
     }
     fFlushState.reset();
 }
 
 void GrDrawingManager::flush() {
-    if (fFlushing) {
+    if (fFlushing || this->abandoned()) {
         return;
     }
     fFlushing = true;
 
     SkDEBUGCODE(bool result =) 
                         SkTTopoSort<GrDrawTarget, GrDrawTarget::TopoSortTraits>(&fDrawTargets);
     SkASSERT(result);
 
 #if 0
     for (int i = 0; i < fDrawTargets.count(); ++i) {
@@ skipping 116 matching lines @@
 }
 
 GrDrawContext* GrDrawingManager::drawContext(GrRenderTarget* rt,
                                              const SkSurfaceProps* surfaceProps) {
     if (this->abandoned()) {
         return nullptr;
     }
 
     return new GrDrawContext(this, rt, surfaceProps, fContext->getAuditTrail(), fSingleOwner);
 }