Re-land "Perform Vulkan resets in a background thread"

Bug: skia:
Change-Id: I1c7ec365a370137ca64d9091cb60e6430c3f1c28
Reviewed-on: https://skia-review.googlesource.com/c/177069
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/src/gpu/vk/GrVkSemaphore.h b/src/gpu/vk/GrVkSemaphore.h
index 6873559..3373ff8 100644
--- a/src/gpu/vk/GrVkSemaphore.h
+++ b/src/gpu/vk/GrVkSemaphore.h
@@ -71,7 +71,7 @@
         }
 #endif
     private:
-        void freeGPUData(const GrVkGpu* gpu) const override;
+        void freeGPUData(GrVkGpu* gpu) const override;
 
         static SkMutex* GetMutex() {
             static SkMutex kMutex;