Make sure we check the version number of Vulkan Extensions.

Bug: skia:
Change-Id: Iff02911491cc61e39f94370c644b6666e5f9118f
Reviewed-on: https://skia-review.googlesource.com/137881
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/vk/GrVkGpu.cpp b/src/gpu/vk/GrVkGpu.cpp
index 5a19713..6a37c27 100644
--- a/src/gpu/vk/GrVkGpu.cpp
+++ b/src/gpu/vk/GrVkGpu.cpp
@@ -37,6 +37,7 @@
 #include "SkSLCompiler.h"
 #include "SkTo.h"
 
+#include "vk/GrVkExtensions.h"
 #include "vk/GrVkTypes.h"
 
 #include <utility>