Add discard API to SkCanvas, plumb it to glDiscardFramebuffer()

src/gpu/GrRenderTarget.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 "GrRenderTarget.h"
@@ skipping 36 matching lines @@
 
 void GrRenderTarget::resolve() {
     // go through context so that all necessary flushing occurs
     GrContext* context = this->getContext();
     if (NULL == context) {
         return;
     }
     context->resolveRenderTarget(this);
 }
 
+void GrRenderTarget::discard() {
+    // go through context so that all necessary flushing occurs
+    GrContext* context = this->getContext();
+    if (NULL == context) {
+        return;
+    }
+    context->discardRenderTarget(this);
+}
+
 size_t GrRenderTarget::sizeInBytes() const {
     size_t colorBits;
     if (kUnknown_GrPixelConfig == fDesc.fConfig) {
         colorBits = 32; // don't know, make a guess
     } else {
         colorBits = GrBytesPerPixel(fDesc.fConfig);
     }
     uint64_t size = fDesc.fWidth;
     size *= fDesc.fHeight;
     size *= colorBits;
@@ skipping 33 matching lines @@
     this->setStencilBuffer(NULL);
 
     INHERITED::onRelease();
 }
 
 void GrRenderTarget::onAbandon() {
     this->setStencilBuffer(NULL);
 
     INHERITED::onAbandon();
 }