Vulkan: Move image layout into helper.

Now that we're using the helper everywhere, we can clean up the
vk::Image class and move the layout tracking into ImageHelper.

Bug: angleproject:2318
Change-Id: I9636835a2a3a76f181dac629bd4182bc5815cdee
Reviewed-on: https://chromium-review.googlesource.com/980774
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Frank Henigman <fjhenigman@chromium.org>
diff --git a/src/libANGLE/renderer/vulkan/RenderbufferVk.cpp b/src/libANGLE/renderer/vulkan/RenderbufferVk.cpp
index ee24d07..b7e363e 100644
--- a/src/libANGLE/renderer/vulkan/RenderbufferVk.cpp
+++ b/src/libANGLE/renderer/vulkan/RenderbufferVk.cpp
@@ -97,18 +97,13 @@
         vk::CommandBuffer *commandBuffer = nullptr;
         ANGLE_TRY(beginWriteResource(renderer, &commandBuffer));
 
-        mImage.getImage().changeLayoutWithStages(aspect, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL,
-                                                 VK_PIPELINE_STAGE_ALL_COMMANDS_BIT,
-                                                 VK_PIPELINE_STAGE_TRANSFER_BIT, commandBuffer);
-
         if (isDepthOrStencilFormat)
         {
-            commandBuffer->clearSingleDepthStencilImage(mImage.getImage(), aspect,
-                                                        kDefaultClearDepthStencilValue);
+            mImage.clearDepthStencil(aspect, kDefaultClearDepthStencilValue, commandBuffer);
         }
         else
         {
-            commandBuffer->clearSingleColorImage(mImage.getImage(), kBlackClearColorValue);
+            mImage.clearColor(kBlackClearColorValue, commandBuffer);
         }
     }