Setup system in Vulkan to reuse VkDescriptorSet allocations.

src/gpu/vk/GrVkPipelineState.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 GrVkPipelineState_DEFINED
 #define GrVkPipelineState_DEFINED
 
 #include "GrStencilSettings.h"
 #include "GrVkImage.h"
 #include "GrVkProgramDesc.h"
 #include "GrVkPipelineStateDataManager.h"
 #include "glsl/GrGLSLProgramBuilder.h"
 
 #include "vk/GrVkDefines.h"
 
 class GrPipeline;
 class GrVkCommandBuffer;
 class GrVkDescriptorPool;
+class GrVkDescriptorSet;
 class GrVkGpu;
 class GrVkImageView;
 class GrVkPipeline;
 class GrVkSampler;
 class GrVkUniformBuffer;
 
 /**
  * This class holds onto a GrVkPipeline object that we use for draws. Besides storing the acutal
  * GrVkPipeline object, this class is also responsible handling all uniforms, descriptors, samplers,
  * and other similar objects that are used along with the VkPipeline in the draw. This includes both
@@ skipping 216 matching lines @@
     // command buffer execution. Thus this is not need to be a GrVkResource.
     VkPipelineLayout fPipelineLayout;
 
     // The DescriptorSets need to survive until the gpu has finished all draws that use them.
     // However, they will only be freed by the descriptor pool. Thus by simply keeping the
     // descriptor pool alive through the draw, the descritor sets will also stay alive. Thus we do
     // not need a GrVkResource versions of VkDescriptorSet. We hold on to these in the
     // GrVkPipelineState since we update the descriptor sets and bind them at separate times;
     VkDescriptorSet fDescriptorSets[2];
 
+    // Once we move samplers over to use the resource provider for descriptor sets we will not need
+    // the above array and instead just use GrVkDescriptorSet like the uniform one here.
+    const GrVkDescriptorSet* fUniformDescriptorSet;
+
     // Meta data so we know which descriptor sets we are using and need to bind.
     int fStartDS;
     int fDSCount;
 
     SkAutoTDelete<GrVkUniformBuffer> fVertexUniformBuffer;
     SkAutoTDelete<GrVkUniformBuffer> fFragmentUniformBuffer;
 
     // GrVkResources used for sampling textures
     SkTDArray<GrVkSampler*> fSamplers;
     SkTDArray<const GrVkImageView*> fTextureViews;
     SkTDArray<const GrVkResource*> fTextures;
 
     // Tracks the current render target uniforms stored in the vertex buffer.
     RenderTargetState fRenderTargetState;
     BuiltinUniformHandles fBuiltinUniformHandles;
 
     // Processors in the GrVkPipelineState
     SkAutoTDelete<GrGLSLPrimitiveProcessor> fGeometryProcessor;
     SkAutoTDelete<GrGLSLXferProcessor> fXferProcessor;
     GrGLSLFragProcs fFragmentProcessors;
 
     Desc fDesc;
 
     GrVkPipelineStateDataManager fDataManager;
 
     DescriptorPoolManager fSamplerPoolManager;
-    const GrVkDescriptorPool*   fCurrentUniformDescPool;
 
     int fNumSamplers;
 
     friend class GrVkPipelineStateBuilder;
 };
 
 #endif