Refactor Vulkan image, texture, RTs so that create and getter handles match.

include/gpu/vk/GrVkTypes.h

Index: include/gpu/vk/GrVkTypes.h
diff --git a/include/gpu/vk/GrVkTypes.h b/include/gpu/vk/GrVkTypes.h
index 2e6a2556303c19fafe4a4e803dea9f6ba832f055..e2e5aae9cbd45df3c5ae1b58c7e521c5849bf827 100644
--- a/include/gpu/vk/GrVkTypes.h
+++ b/include/gpu/vk/GrVkTypes.h
@@ -27,18 +27,21 @@
 ///////////////////////////////////////////////////////////////////////////////
 /**
  * Types for interacting with Vulkan resources created externally to Skia. GrBackendObjects for 
- * Vulkan textures are really const GrVkTextureInfo*
+ * Vulkan textures are really const GrVkImageInfo*
  */
-
-struct GrVkTextureInfo {
+struct GrVkImageInfo {
     VkImage        fImage;
-    VkDeviceMemory fAlloc;    // this may be null iff the texture is an RT and uses borrow semantics
+    VkDeviceMemory fAlloc;    // can be VK_NULL_HANDLE iff Tex is an RT and uses borrow semantics
     VkImageTiling  fImageTiling;
     VkImageLayout  fImageLayout;
     VkFormat       fFormat;
     uint32_t       fLevelCount;
+
+    // This gives a way for a client to update the layout of the Image if they change the layout
+    // while we're still holding onto the wrapped texture.
+    void updateImageLayout(VkImageLayout layout) { fImageLayout = layout; }

[jvanverth1, 2016/05/13 16:14:40]

I don't understand how this would be used. The original contents of the
ImageInfo struct are copied from the client version to the wrapped texture, so
how do they pass this information down?

[egdaniel, 2016/05/13 18:00:05]

When they call getTextureHandle they will get a pointer to our internal
VkImageInfo. That is when we expect them to update the layout.

 };
 
-GR_STATIC_ASSERT(sizeof(GrBackendObject) >= sizeof(const GrVkTextureInfo*));
+GR_STATIC_ASSERT(sizeof(GrBackendObject) >= sizeof(const GrVkImageInfo*));
 
 #endif