refactor(waitForAngular): improve error messages when timeouts occur

lib/protractor.js

@@ -411,12 +411,24 @@ Protractor.prototype.waitForAngular = function() {
               'sync with the page: ' + JSON.stringify(browserErr);
       }
     }).then(null, function(err) {
-      if (!/asynchronous script timeout/.test(err.message)) {
+      var timeout;
+      if (/asynchronous script timeout/.test(err.message)) {
+        // Timeout on Chrome
+        timeout = /[\d\.]*\ seconds/.exec(err.message);
+      } else if (/Timed out waiting for async script/.test(err.message)) {
+        // Timeout on Firefox
+        timeout = /[\d\.]*ms/.exec(err.message);
+      } else if (/Timed out waiting for an asynchronous script/.test(err.message)) {
+        // Timeout on Safari
+        timeout = /[\d\.]*\ ms/.exec(err.message);
+      }
+      if (timeout) {
+        throw 'Timed out waiting for Protractor to synchronize with ' +
+            'the page after ' + timeout + '. Please see ' +
+            'https://github.com/angular/protractor/blob/master/docs/faq.md';
+      } else {
         throw err;
       }
-      var timeout = /[\d\.]*\ seconds/.exec(err.message);
-      throw 'Timed out waiting for Protractor to synchronize with ' +
-            'the page after ' + timeout;
     });
 };