Skip non-D3D11 test contexts on Windows-on-ARM bots

The device only has D3D11 (no D3D9 or GL), so every unit test
failed to create three of the five context types. This wasn't
causing actual problems, but was filling the logs with a huge
amount of noise.

Bug: skia:9275

Change-Id: I78068b16a56918bc7dba2862834996fb07050438
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/229487
Reviewed-by: Eric Boren <borenet@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
diff --git a/tools/gpu/gl/angle/GLTestContext_angle.cpp b/tools/gpu/gl/angle/GLTestContext_angle.cpp
index d54408d..59430ca 100644
--- a/tools/gpu/gl/angle/GLTestContext_angle.cpp
+++ b/tools/gpu/gl/angle/GLTestContext_angle.cpp
@@ -500,6 +500,14 @@
 
 std::unique_ptr<GLTestContext> MakeANGLETestContext(ANGLEBackend type, ANGLEContextVersion version,
                                                     GLTestContext* shareContext, void* display){
+#if defined(SK_BUILD_FOR_WIN) && defined(_M_ARM64)
+    // Windows-on-ARM only has D3D11. This will fail correctly, but it produces huge amounts of
+    // debug output for every unit test from both ANGLE and our context factory.
+    if (ANGLEBackend::kD3D11 != type) {
+        return nullptr;
+    }
+#endif
+
     ANGLEGLContext* angleShareContext = reinterpret_cast<ANGLEGLContext*>(shareContext);
     std::unique_ptr<GLTestContext> ctx(new ANGLEGLContext(type, version,
                                                           angleShareContext, display));