Make GM render to render targets that are also textures.

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 "effects/GrTextureDomainEffect.h"
@@ skipping 149 matching lines @@
     GrPixelConfig config = renderTarget->config();
 
     bool isOpaque;
     SkBitmap bitmap;
     bitmap.setConfig(grConfig2skConfig(config, &isOpaque),
                      renderTarget->width(), renderTarget->height());
     bitmap.setIsOpaque(isOpaque);
     return bitmap;
 }
 
+SkGpuDevice* SkGpuDevice::Create(GrSurface* surface) {
+    GrAssert(NULL != surface);
+    if (NULL == surface->asRenderTarget() || NULL == surface->getContext()) {
+        return NULL;
+    }
+    if (surface->asTexture()) {
+        return SkNEW_ARGS(SkGpuDevice, (surface->getContext(), surface->asTexture()));
+    } else {
+        return SkNEW_ARGS(SkGpuDevice, (surface->getContext(), surface->asRenderTarget()));
+    }
+}
+
 SkGpuDevice::SkGpuDevice(GrContext* context, GrTexture* texture)
 : SkDevice(make_bitmap(context, texture->asRenderTarget())) {
     this->initFromRenderTarget(context, texture->asRenderTarget(), false);
 }
 
 SkGpuDevice::SkGpuDevice(GrContext* context, GrRenderTarget* renderTarget)
 : SkDevice(make_bitmap(context, renderTarget)) {
     this->initFromRenderTarget(context, renderTarget, false);
 }
 
@@ skipping 1656 matching lines @@
                          GrTexture* texture,
                          bool needClear)
     : SkDevice(make_bitmap(context, texture->asRenderTarget())) {
 
     GrAssert(texture && texture->asRenderTarget());
     // This constructor is called from onCreateCompatibleDevice. It has locked the RT in the texture
     // cache. We pass true for the third argument so that it will get unlocked.
     this->initFromRenderTarget(context, texture->asRenderTarget(), true);
     fNeedClear = needClear;
 }