Fix revision bundling

Summary:
This fixes headless not terminating due to the `package.json` not being readable.
I instead write this to the `global` object in the same way that the version is
set.

Reviewed By: jknoxville

Differential Revision: D14579316

fbshipit-source-id: 238afe912366c423552305e120088f4abac4c20b

static/electron-stubs.notjs

@@ -11,7 +11,8 @@
     },
     app: {
       getVersion: function() {return global.__VERSION__ || '1';},
-      getName: function() {return '';}
+      getName: function() {return '';},
+      getAppPath: function() {return process.cwd();}
     },
     shell: {
       openExternal: function() {}