Add entry point for passing options to the GrContextFactory

gm/gmmain.cpp

Index: gm/gmmain.cpp
diff --git a/gm/gmmain.cpp b/gm/gmmain.cpp
index 9b51eb0ad6265fc9ad57d74a1a78f03909661db7..eb9147b628341b7e70a12fdcb017d3de5db09eef 100644
--- a/gm/gmmain.cpp
+++ b/gm/gmmain.cpp
@@ -2284,7 +2284,7 @@ int tool_main(int argc, char** argv) {
     SkTDArray<SkScalar> tileGridReplayScales;
 #if SK_SUPPORT_GPU
     GrGLStandard gpuAPI = kNone_GrGLStandard;
-    GrContextFactory* grFactory = new GrContextFactory;
+    GrContextFactory* grFactory = new GrContextFactory(GrContext::Options());
 #else
     GrGLStandard gpuAPI = 0;
     GrContextFactory* grFactory = NULL;