Set ASCII as the default bundle encoding

Reviewed By: davidaurelio

Differential Revision: D2596387

fb-gh-sync-id: deadb8e9a44bbe7b12ce9e6bb5e3c96d4f646074

react-packager/src/Bundler/Bundle.js

@@ -134,6 +134,7 @@ class Bundle {
         fromString: true,
         outSourceMap: 'bundle.js',
         inSourceMap: this.getSourceMap(),
+        output: {ascii_only: true},
       });
       Activity.endEvent(minifyActivity);
       return this._minifiedSourceAndMap;