Set the "mutable format" bit on sRGB images at creation time.

src/gpu/vk/GrVkImage.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrVkGpu.h"
 #include "GrVkImage.h"
 #include "GrVkMemory.h"
@@ skipping 59 matching lines @@
 
     // Create Image
     VkSampleCountFlagBits vkSamples;
     if (!GrSampleCountToVkSampleCount(imageDesc.fSamples, &vkSamples)) {
         return false;
     }
 
     SkASSERT(VK_IMAGE_TILING_OPTIMAL == imageDesc.fImageTiling ||
              VK_SAMPLE_COUNT_1_BIT == vkSamples);
 
+    // sRGB format images may need to be aliased to linear for various reasons (legacy mode):
+    VkImageCreateFlags createFlags = GrVkFormatIsSRGB(imageDesc.fFormat, nullptr)
+        ? VK_IMAGE_CREATE_MUTABLE_FORMAT_BIT : 0;
+
     const VkImageCreateInfo imageCreateInfo = {
         VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO,         // sType
         NULL,                                        // pNext
-        0,                                           // VkImageCreateFlags
+        createFlags,                                 // VkImageCreateFlags
         imageDesc.fImageType,                        // VkImageType
         imageDesc.fFormat,                           // VkFormat
         { imageDesc.fWidth, imageDesc.fHeight, 1 },  // VkExtent3D
         imageDesc.fLevels,                           // mipLevels
         1,                                           // arrayLayers
         vkSamples,                                   // samples
         imageDesc.fImageTiling,                      // VkImageTiling
         imageDesc.fUsageFlags,                       // VkImageUsageFlags
         VK_SHARING_MODE_EXCLUSIVE,                   // VkSharingMode
         0,                                           // queueFamilyCount
@@ skipping 46 matching lines @@
     }
 }
 
 void GrVkImage::Resource::freeGPUData(const GrVkGpu* gpu) const {
     VK_CALL(gpu, DestroyImage(gpu->device(), fImage, nullptr));
     VK_CALL(gpu, FreeMemory(gpu->device(), fAlloc, nullptr));
 }
 
 void GrVkImage::BorrowedResource::freeGPUData(const GrVkGpu* gpu) const {
 }