Implement initCopySurfaceDstDesc for Vulkan

src/gpu/vk/GrVkGpu.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 "GrVkGpu.h"
 
 #include "GrContextOptions.h"
@@ skipping 1286 matching lines @@
     }
 
     if (can_copy_as_draw(dst, src, this)) {
         this->copySurfaceAsDraw(dst, src, srcRect, dstPoint);
         return true;
     }
 
     return false;
 }
 
+bool GrVkGpu::initCopySurfaceDstDesc(const GrSurface* src, GrSurfaceDesc* desc) const {
+    // Currently we don't support msaa
+    if (src->asRenderTarget() && src->asRenderTarget()->numColorSamples() > 1) {
+        return false;
+    }
+
+    // This will support copying the dst as CopyImage since all of our surfaces require transferSrc
+    // and transferDst usage flags in Vulkan.
+    desc->fOrigin = src->origin();
+    desc->fConfig = src->config();
+    desc->fFlags = kNone_GrSurfaceFlags;
+    return true;
+}
+
 void GrVkGpu::onGetMultisampleSpecs(GrRenderTarget* rt, const GrStencilSettings&,
                                     int* effectiveSampleCnt, SkAutoTDeleteArray<SkPoint>*) {
     // TODO: stub.
     SkASSERT(!this->caps()->sampleLocationsSupport());
     *effectiveSampleCnt = rt->desc().fSampleCnt;
 }
 
 bool GrVkGpu::onGetReadPixelsInfo(GrSurface* srcSurface, int width, int height, size_t rowBytes,
                                   GrPixelConfig readConfig, DrawPreference* drawPreference,
                                   ReadPixelTempDrawInfo* tempDrawInfo) {
@@ skipping 249 matching lines @@
     aglSwapBuffers(aglGetCurrentContext());
     int set_a_break_pt_here = 9;
     aglSwapBuffers(aglGetCurrentContext());
 #elif defined(SK_BUILD_FOR_WIN32)
     SwapBuf();
     int set_a_break_pt_here = 9;
     SwapBuf();
 #endif
 #endif
 }