Vulkan: Encapsulate RenderTargetVk.

This makes the members private and adds more functionality. This moves
more responsibility out of vk::CommandGraphNode and also makes the
RenderPass init in the CommandGraphNode class better encapsulated.

Bug: angleproject:2539
Change-Id: Ia16f3f39cf011548c6473805b8b28e284808e856
Reviewed-on: https://chromium-review.googlesource.com/1040279
Reviewed-by: Luc Ferron <lucferron@chromium.org>
Reviewed-by: Frank Henigman <fjhenigman@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/renderer/vulkan/CommandGraph.h b/src/libANGLE/renderer/vulkan/CommandGraph.h
index 235d9d5..b44269d 100644
--- a/src/libANGLE/renderer/vulkan/CommandGraph.h
+++ b/src/libANGLE/renderer/vulkan/CommandGraph.h
@@ -107,13 +107,9 @@
     // storeRenderPassInfo and append*RenderTarget store info relevant to the RenderPass.
     void storeRenderPassInfo(const Framebuffer &framebuffer,
                              const gl::Rectangle renderArea,
+                             const vk::RenderPassDesc &renderPassDesc,
                              const std::vector<VkClearValue> &clearValues);
 
-    // storeRenderPassInfo and append*RenderTarget store info relevant to the RenderPass.
-    // Note: RenderTargets must be added in order, with the depth/stencil being added last.
-    void appendColorRenderTarget(Serial serial, RenderTargetVk *colorRenderTarget);
-    void appendDepthStencilRenderTarget(Serial serial, RenderTargetVk *depthStencilRenderTarget);
-
     // Dependency commands order node execution in the command graph.
     // Once a node has commands that must happen after it, recording is stopped and the node is
     // frozen forever.