Add GrVkTexelBuffer class

Bug: skia:
Change-Id: I6111902f58df3af92702d974a52d9c7f267634d4
Reviewed-on: https://skia-review.googlesource.com/15628
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
diff --git a/src/gpu/vk/GrVkBuffer.h b/src/gpu/vk/GrVkBuffer.h
index e58d5e4..6d0c1fd 100644
--- a/src/gpu/vk/GrVkBuffer.h
+++ b/src/gpu/vk/GrVkBuffer.h
@@ -43,6 +43,7 @@
         kVertex_Type,
         kIndex_Type,
         kUniform_Type,
+        kTexel_Type,
         kCopyRead_Type,
         kCopyWrite_Type,
     };