Fix a race which took us to the directory on load sometimes (#2602)

Sometimes window.onload would run before loadApp had finished (specifically, if
the browser had to wait for config.json to load). Avoid the race by moving all
of the onload logic into loadApp.

src/vector/index.js

@@ -120,6 +120,8 @@ var lastLoadedScreen = null;
 // so a web page can update the URL bar appropriately.
 var onNewScreen = function(screen) {
     console.log("newscreen "+screen);
+    // just remember the most recent screen while we are loading, so that the
+    // user doesn't see the URL bar doing a dance
     if (!loaded) {
         lastLoadedScreen = screen;
     } else {
@@ -156,19 +158,6 @@ function getDefaultDeviceDisplayName() {
 }
 
 window.addEventListener('hashchange', onHashChange);
-window.onload = function() {
-    console.log("window.onload");
-    if (!validBrowser) {
-        return;
-    }
-    UpdateChecker.start();
-    routeUrl(window.location);
-    loaded = true;
-    if (lastLoadedScreen) {
-        onNewScreen(lastLoadedScreen);
-        lastLoadedScreen = null;
-    }
-}
 
 function getConfig() {
     let deferred = q.defer();
@@ -259,6 +248,8 @@ async function loadApp() {
             Unable to load config file: please refresh the page to try again.
         </div>, document.getElementById('matrixchat'));
     } else if (validBrowser) {
+        UpdateChecker.start();
+
         var MatrixChat = sdk.getComponent('structures.MatrixChat');
 
         window.matrixChat = ReactDOM.render(
@@ -275,6 +266,15 @@ async function loadApp() {
             />,
             document.getElementById('matrixchat')
         );
+
+        routeUrl(window.location);
+
+        // we didn't propagate screen changes to the URL bar while we were loading; do it now.
+        loaded = true;
+        if (lastLoadedScreen) {
+            onNewScreen(lastLoadedScreen);
+            lastLoadedScreen = null;
+        }
     }
     else {
         console.error("Browser is missing required features.");
@@ -285,7 +285,6 @@ async function loadApp() {
                 validBrowser = true;
                 console.log("User accepts the compatibility risks.");
                 loadApp();
-                window.onload(); // still do the same code paths for compatible clients
             }} />,
             document.getElementById('matrixchat')
         );