Fixed test breakage from 501f9701cd

Unlike iOS, OS X does not consider OpenGL.framework to be a standard library, so LINK_WITH_STANDARD_LIBRARIES does not pull it in.

Ref #1099, #1105

gyp/platform-osx.gypi

@@ -28,6 +28,7 @@
         'ldflags': [
           '-framework ImageIO',
           '-framework CoreServices',
+          '-framework OpenGL',
           '-framework ApplicationServices',
         ],
       },