remove fClipStack and attach/deattach-from-canvas

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 269 matching lines @@
     fRenderTarget->writePixels(x, y, info.width(), info.height(), config, pixels, rowBytes, flags);
 
     return true;
 }
 
 bool SkGpuDevice::onAccessPixels(SkPixmap* pmap) {
     ASSERT_SINGLE_OWNER
     return false;
 }
 
-void SkGpuDevice::onAttachToCanvas(SkCanvas* canvas) {
-    ASSERT_SINGLE_OWNER
-    INHERITED::onAttachToCanvas(canvas);
-
-    // Canvas promises that this ptr is valid until onDetachFromCanvas is called
-    fClipStack.reset(SkRef(canvas->getClipStack()));
-}
-
-void SkGpuDevice::onDetachFromCanvas() {
-    ASSERT_SINGLE_OWNER
-    INHERITED::onDetachFromCanvas();
-    fClip.reset();
-    fClipStack.reset(nullptr);
-}
-
 // call this every draw call, to ensure that the context reflects our state,
 // and not the state from some other canvas/device
 void SkGpuDevice::prepareDraw(const SkDraw& draw) {
     ASSERT_SINGLE_OWNER
-    SkASSERT(fClipStack.get());
 
-    SkASSERT(draw.fClipStack && draw.fClipStack == fClipStack);
-
-    fClip.reset(fClipStack, &this->getOrigin());
+    fClip.reset(draw.fClipStack, &this->getOrigin());
 }
 
 GrDrawContext* SkGpuDevice::accessDrawContext() {
     ASSERT_SINGLE_OWNER
     return fDrawContext.get();
 }
 
 void SkGpuDevice::clearAll() {
     ASSERT_SINGLE_OWNER
     GrColor color = 0;
@@ skipping 1546 matching lines @@
 }
 
 SkImageFilterCache* SkGpuDevice::getImageFilterCache() {
     ASSERT_SINGLE_OWNER
     // We always return a transient cache, so it is freed after each
     // filter traversal.
     return SkImageFilterCache::Create(kDefaultImageFilterCacheSize);
 }
 
 #endif