Use single alloc for vulkan optimal image heaps to fix memory crash

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 117 matching lines @@
                                                                &fCmdPool));
 
     // must call this after creating the CommandPool
     fResourceProvider.init();
     fCurrentCmdBuffer = fResourceProvider.createPrimaryCommandBuffer();
     SkASSERT(fCurrentCmdBuffer);
     fCurrentCmdBuffer->begin(this);
 
     // set up our heaps
     fHeaps[kLinearImage_Heap].reset(new GrVkHeap(this, GrVkHeap::kSubAlloc_Strategy, 16*1024*1024));
-    fHeaps[kOptimalImage_Heap].reset(new GrVkHeap(this, GrVkHeap::kSubAlloc_Strategy, 64*1024*1024));
+    // We want the OptimalImage_Heap to use a SubAlloc_strategy but it occasionally causes the
+    // device to run out of memory. Most likely this is caused by fragmentation in the device heap
+    // and we can't allocate more. Until we get a fix moving this to SingleAlloc.
+    fHeaps[kOptimalImage_Heap].reset(new GrVkHeap(this, GrVkHeap::kSingleAlloc_Strategy, 64*1024*1024));
     fHeaps[kSmallOptimalImage_Heap].reset(new GrVkHeap(this, GrVkHeap::kSubAlloc_Strategy, 2*1024*1024));
     fHeaps[kVertexBuffer_Heap].reset(new GrVkHeap(this, GrVkHeap::kSingleAlloc_Strategy, 0));
     fHeaps[kIndexBuffer_Heap].reset(new GrVkHeap(this, GrVkHeap::kSingleAlloc_Strategy, 0));
     fHeaps[kUniformBuffer_Heap].reset(new GrVkHeap(this, GrVkHeap::kSubAlloc_Strategy, 64*1024));
     fHeaps[kCopyReadBuffer_Heap].reset(new GrVkHeap(this, GrVkHeap::kSingleAlloc_Strategy, 0));
     fHeaps[kCopyWriteBuffer_Heap].reset(new GrVkHeap(this, GrVkHeap::kSubAlloc_Strategy, 16*1024*1024));
 }
 
 GrVkGpu::~GrVkGpu() {
     fCurrentCmdBuffer->end(this);
@@ skipping 1557 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
 }