Some Vulkan memory fixes and cleanup

src/gpu/vk/GrVkBuffer.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 "GrVkBuffer.h"
 #include "GrVkGpu.h"
 #include "GrVkMemory.h"
@@ skipping 27 matching lines @@
         case kUniform_Type:
             bufInfo.usage = VK_BUFFER_USAGE_UNIFORM_BUFFER_BIT;
             break;
         case kCopyRead_Type:
             bufInfo.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT;
             break;
         case kCopyWrite_Type:
             bufInfo.usage = VK_BUFFER_USAGE_TRANSFER_DST_BIT;
             break;
     }
-    bufInfo.usage |= VK_BUFFER_USAGE_TRANSFER_DST_BIT;
+    if (!desc.fDynamic) {
+        bufInfo.usage |= VK_BUFFER_USAGE_TRANSFER_DST_BIT;
+    }
 
     bufInfo.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
     bufInfo.queueFamilyIndexCount = 0;
     bufInfo.pQueueFamilyIndices = nullptr;
 
     VkResult err;
     err = VK_CALL(gpu, CreateBuffer(gpu->device(), &bufInfo, nullptr, &buffer));
     if (err) {
         return nullptr;
     }
@@ skipping 154 matching lines @@
     this->internalUnmap(gpu, srcSizeInBytes);
 
     return true;
 }
 
 void GrVkBuffer::validate() const {
     SkASSERT(!fResource || kVertex_Type == fDesc.fType || kIndex_Type == fDesc.fType
              || kCopyRead_Type == fDesc.fType || kCopyWrite_Type == fDesc.fType
              || kUniform_Type == fDesc.fType);
 }