Fix pushState exception when run inside Chrome Apps (fixes #601) (#621)

Author: benvinegar

src/raven.js

@@ -889,7 +889,13 @@ Raven.prototype = {
         }
 
         // record navigation (URL) changes
-        if ('history' in window && history.pushState) {
+        // NOTE: in Chrome App environment, touching history.pushState, *even inside
+        //       a try/catch block*, will cause Chrome to output an error to console.error
+        // borrowed from: https://github.com/angular/angular.js/pull/13945/files
+        var chrome = window.chrome;
+        var isChromePackagedApp = chrome && chrome.app && chrome.app.runtime;
+        var hasPushState = !isChromePackagedApp && window.history && history.pushState;
+        if (hasPushState) {
             // TODO: remove onpopstate handler on uninstall()
             var oldOnPopState = window.onpopstate;
             window.onpopstate = function () {