Add MaxAPIVersion to GrVkBackendContext.

This moves us to the correct way of handling the correct version of
Vulkan that the client wants us to use.

Bug: skia:
Change-Id: I6c7962b5d2d48ae142c6a701c30f5af3801ac99b
Reviewed-on: https://skia-review.googlesource.com/c/187382
Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
diff --git a/include/gpu/vk/GrVkBackendContext.h b/include/gpu/vk/GrVkBackendContext.h
index f49c36f..8617603 100644
--- a/include/gpu/vk/GrVkBackendContext.h
+++ b/include/gpu/vk/GrVkBackendContext.h
@@ -49,7 +49,10 @@
     VkQueue                    fQueue;
     uint32_t                   fGraphicsQueueIndex;
     uint32_t                   fMinAPIVersion; // Deprecated. Set fInstanceVersion instead.
-    uint32_t                   fInstanceVersion = 0;
+    uint32_t                   fInstanceVersion = 0; // Deprecated. Set fMaxApiVersion instead.
+    // The max api version set here should match the value set in VkApplicationInfo::apiVersion when
+    // then VkInstance was created.
+    uint32_t                   fMaxAPIVersion = 0;
     uint32_t                   fExtensions = 0; // Deprecated. Use fVkExtensions instead.
     const GrVkExtensions*      fVkExtensions = nullptr;
     uint32_t                   fFeatures; // Deprecated. Use either fDeviceFeatures[2] instead.