Use a D3D11 renderer by default, when available.

Also update SampleApplication to request the default
renderer instead of explicitely asking for d3d11

BUG=angleproject:892

Change-Id: I70c431b3c1ba78c3ce7844d7f276cc19ac17d7f5
Reviewed-on: https://chromium-review.googlesource.com/269999
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/samples/sample_util/SampleApplication.h b/samples/sample_util/SampleApplication.h
index 47ef544..3acfb59 100644
--- a/samples/sample_util/SampleApplication.h
+++ b/samples/sample_util/SampleApplication.h
@@ -24,7 +24,7 @@
 {
   public:
     SampleApplication(const std::string& name, size_t width, size_t height,
-                      EGLint glesMajorVersion = 2, EGLint requestedRenderer = EGL_PLATFORM_ANGLE_TYPE_D3D11_ANGLE);
+                      EGLint glesMajorVersion = 2, EGLint requestedRenderer = EGL_PLATFORM_ANGLE_TYPE_DEFAULT_ANGLE);
     virtual ~SampleApplication();
 
     virtual bool initialize();