Remove unused render target members from GL and VK sk_app::WindowContext classes

tools/viewer/sk_app/VulkanWindowContext.h

 
 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef VulkanWindowContext_DEFINED
 #define VulkanWindowContext_DEFINED
 
@@ skipping 79 matching lines @@
     VkPtr<PFN_vkCreateSharedSwapchainsKHR> fCreateSharedSwapchainsKHR;
 
     VkSurfaceKHR      fSurface;
     VkSwapchainKHR    fSwapchain;
     uint32_t          fPresentQueueIndex;
     VkQueue           fPresentQueue;
 
     uint32_t               fImageCount;
     VkImage*               fImages;         // images in the swapchain
     VkImageLayout*         fImageLayouts;   // layouts of these images when not color attachment
-    sk_sp<GrRenderTarget>* fRenderTargets;  // wrapped rendertargets for those images
     sk_sp<SkSurface>*      fSurfaces;       // surfaces client renders to (may not be based on rts)
     VkCommandPool          fCommandPool;
     BackbufferInfo*        fBackbuffers;
     uint32_t               fCurrentBackbufferIndex;
 };
 
 }   // namespace sk_app
 
 #endif // SK_VULKAN
 
 #endif