Limit lifetime of GrDrawContext objects

src/gpu/SkGpuDevice.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGpuDevice.h"
 
 #include "GrBlurUtils.h"
@@ skipping 178 matching lines @@
     fOpaque = SkToBool(flags & kIsOpaque_Flag);
 
     fRenderTarget = SkRef(rt);
 
     SkAlphaType at = fOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType;
     SkImageInfo info = rt->surfacePriv().info(at).makeWH(width, height);
     SkPixelRef* pr = new SkGrPixelRef(info, rt);
     fLegacyBitmap.setInfo(info);
     fLegacyBitmap.setPixelRef(pr)->unref();
 
-    fDrawContext.reset(SkRef(fContext->drawContext(&this->surfaceProps())));
+    fDrawContext.reset(fContext->drawContext(&this->surfaceProps()));
 }
 
 GrRenderTarget* SkGpuDevice::CreateRenderTarget(GrContext* context, SkSurface::Budgeted budgeted,
                                                 const SkImageInfo& origInfo, int sampleCount) {
     if (kUnknown_SkColorType == origInfo.colorType() ||
         origInfo.width() < 0 || origInfo.height() < 0) {
         return nullptr;
     }
 
     if (!context) {
@@ skipping 156 matching lines @@
     fRenderTarget = newRT.detach();
 
 #ifdef SK_DEBUG
     SkImageInfo info = fRenderTarget->surfacePriv().info(fOpaque ? kOpaque_SkAlphaType :
                                                                    kPremul_SkAlphaType);
     SkASSERT(info == fLegacyBitmap.info());
 #endif
     SkPixelRef* pr = new SkGrPixelRef(fLegacyBitmap.info(), fRenderTarget);
     fLegacyBitmap.setPixelRef(pr)->unref();
 
-    fDrawContext.reset(SkRef(fRenderTarget->getContext()->drawContext(&this->surfaceProps())));
+    fDrawContext.reset(fRenderTarget->getContext()->drawContext(&this->surfaceProps()));
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 void SkGpuDevice::drawPaint(const SkDraw& draw, const SkPaint& paint) {
     CHECK_SHOULD_DRAW(draw);
     GR_CREATE_TRACE_MARKER_CONTEXT("SkGpuDevice::drawPaint", fContext);
 
     GrPaint grPaint;
     if (!SkPaint2GrPaint(this->context(), fRenderTarget, paint, *draw.fMatrix, true, &grPaint)) {
@@ skipping 1513 matching lines @@
 #endif
 }
 
 SkImageFilter::Cache* SkGpuDevice::getImageFilterCache() {
     // We always return a transient cache, so it is freed after each
     // filter traversal.
     return SkImageFilter::Cache::Create(kDefaultImageFilterCacheSize);
 }
 
 #endif