return false if the typeface cannot be found
from https://codereview.appspot.com/5756059/



git-svn-id: http://skia.googlecode.com/svn/trunk@3340 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gm/gammatext.cpp b/gm/gammatext.cpp
index 8a655f4..6f1c298 100644
--- a/gm/gammatext.cpp
+++ b/gm/gammatext.cpp
@@ -29,6 +29,7 @@
         paint->setTypeface(tf)->unref();
         return true;
     }
+    return false;
 }
 
 #ifdef SK_BUILD_FOR_MAC