Add unit test to check if we can create a VkDevice using global priority extension.

Bug: b/126595186
Change-Id: I0a23ca2a7cc47bd02bb535566aa37627899249ee
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/197201
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Stan Iliev <stani@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
diff --git a/gn/tests.gni b/gn/tests.gni
index c3901af..fa9ff81 100644
--- a/gn/tests.gni
+++ b/gn/tests.gni
@@ -287,6 +287,7 @@
   "$_tests/VkDrawableTest.cpp",
   "$_tests/VkHardwareBufferTest.cpp",
   "$_tests/VkMakeCopyPipelineTest.cpp",
+  "$_tests/VkPriorityExtensionTest.cpp",
   "$_tests/VkWrapTests.cpp",
   "$_tests/VptrTest.cpp",
   "$_tests/WindowRectanglesTest.cpp",