Performing key/cert sync and generation while the arrow animation is being done.

Hopefully this minimizes the amount of delay the user notices.

browserid/static/dialog/controllers/dialog_controller.js

@@ -95,8 +95,8 @@ PageController.extend("Dialog", {}, {
         self.doConfirmUser(info.email);
       });
 
-      hub.subscribe("email_chosen", function(msg, info) {
-        self.doEmailSelected(info.email);
+      hub.subscribe("assertion_generated", function(msg, info) {
+        self.doAssertionGenerated(info.assertion);
       });
 
       hub.subscribe("email_staged", function(msg, info) {
@@ -180,19 +180,18 @@ PageController.extend("Dialog", {}, {
     },
 
     doEmailConfirmed: function() {
-      this.doEmailSelected(this.confirmEmail);
+      var self=this;
+      // yay!  now we need to produce an assertion.
+      BrowserID.Identities.getAssertion(this.confirmEmail, self.doAssertionGenerated.bind(self));
     },
 
-    doEmailSelected: function(email) {
+    doAssertionGenerated: function(assertion) {
       var self=this;
-      // yay!  now we need to produce an assertion.
-      BrowserID.Identities.getAssertion(email, function(assertion) {
-        // Clear onerror before the call to onsuccess - the code to onsuccess 
-        // calls window.close, which would trigger the onerror callback if we 
-        // tried this afterwards.
-        self.onerror = null;
-        self.onsuccess(assertion);
-      });
+      // Clear onerror before the call to onsuccess - the code to onsuccess 
+      // calls window.close, which would trigger the onerror callback if we 
+      // tried this afterwards.
+      self.onerror = null;
+      self.onsuccess(assertion);
     },
 
     doNotMe: function() {

browserid/static/dialog/controllers/pickemail_controller.js

@@ -78,14 +78,31 @@
   }
 
   function signIn() {
-    var self=this;
+    var self=this,
+        animationComplete = false,
+        assertion,
+        email = $("input[type=radio]:checked").val();
+
+    function onComplete() {
+      if(assertion && animationComplete) {
+        self.close("assertion_generated", {
+          assertion: assertion
+        });
+      }
+    }
+
+    // Kick of the assertion fetching/keypair generating while we are shoing 
+    // the animation, hopefully this minimizes the delay the user notices.
+    identities.getAssertion(email, function(assert) {
+      assertion = assert;
+      onComplete();
+    });
+
     $("#signIn").animate({"width" : "685px"}, "slow", function () {
       // post animation
        $("body").delay(500).animate({ "opacity" : "0.5"}, "fast", function () {
-          var email = $("input[type=radio]:checked").val();
-          self.close("email_chosen", {
-            email: email
-          });
+         animationComplete = true;
+         onComplete();
        });
     }); 
   }