Submit button added to user pod.

ui/login/account_picker/user_pod_row.js

Index: ui/login/account_picker/user_pod_row.js
diff --git a/ui/login/account_picker/user_pod_row.js b/ui/login/account_picker/user_pod_row.js
index dbf03e91657250ff9b917a4631318018737ffcf5..e96521453eebd758c94a40bc9a450aaa474d6db1 100644
--- a/ui/login/account_picker/user_pod_row.js
+++ b/ui/login/account_picker/user_pod_row.js
@@ -757,6 +757,8 @@ cr.define('login', function() {
           this.handlePasswordKeyPress_.bind(this));
       this.passwordElement.addEventListener('input',
           this.handleInputChanged_.bind(this));
+      this.submitButton.addEventListener('click',
+          this.handleSubmitButtonClick_.bind(this));
 
       this.imageElement.addEventListener('load',
           this.parentNode.handlePodImageLoad.bind(this.parentNode, this));
@@ -766,6 +768,17 @@ cr.define('login', function() {
       this.setAuthType(initialAuthType, null);
 
       this.userClickAuthAllowed_ = false;
+
+      // Lazy load the assets needed for the polymer submit button.
+      if (cr.ui.login.ResourceLoader.alreadyLoadedAssets('userpod-polymer'))

[jdufault, 2016/08/30 19:50:40]

Use id 'custom-elements-user-pod'

[jdufault, 2016/08/30 19:50:40]

I'd invert the if condition so it is

  if (!loadedAssets) {
    register();
    loadOnIdle();
  }

[sammiequon, 2016/08/30 20:52:35]

Done.

[sammiequon, 2016/08/30 20:52:35]

Done.

+          return;
+
+      cr.ui.login.ResourceLoader.registerAssets({
+          id: 'userpod-polymer',
+          html: [{ url: 'chrome://oobe/custom_elements_user_pod.html'}]

[jdufault, 2016/08/30 19:50:40]

space before }]

[sammiequon, 2016/08/30 20:52:35]

Done.

+       });
+      cr.ui.login.ResourceLoader.loadAssetsOnIdle('userpod-polymer',
+          function() {});

[jdufault, 2016/08/30 19:50:40]

Remove empty function.

[sammiequon, 2016/08/30 20:52:35]

Done.

     },
 
     /**
@@ -793,6 +806,14 @@ cr.define('login', function() {
     },
 
     /**
+     * Handles a click event on submit button.
+     * @param {Event} e Click event.
+     */
+    handleSubmitButtonClick_: function(e) {
+      this.parentNode.setActivatedPod(this, e);
+    },
+
+    /**
      * Top edge margin number of pixels.
      * @type {?number}
      */
@@ -870,6 +891,14 @@ cr.define('login', function() {
     },
 
     /**
+     * Gets submit button.
+     * @type {!HTMLInputElement}
+     */
+    get submitButton() {
+      return this.querySelector('.submit-button');
+    },
+
+    /**
      * Gets the password label, which is used to show a message where the
      * password field is normally.
      * @type {!HTMLInputElement}
@@ -1103,6 +1132,10 @@ cr.define('login', function() {
       return this.pinKeyboard && this.pinKeyboard.offsetHeight > 0;
     },
 
+    setErrorDisplay: function(visible) {
+      this.submitButton.classList.toggle('error-shown', visible);
+    },
+
     toggleTransitions: function(enable) {
       this.classList.toggle('flying-pin-pod', enable);
     },
@@ -1830,6 +1863,8 @@ cr.define('login', function() {
     handleInputChanged_: function(e) {
       if (this.pinKeyboard)
         this.pinKeyboard.value = this.passwordElement.value;
+      this.submitButton.disabled = this.passwordElement.value.length <= 0;
+      this.setErrorDisplay(false);
     },
 
     /**
@@ -2604,11 +2639,28 @@ cr.define('login', function() {
       userPod.initialize();
     },
 
+    /**
+     * Enables or disables transitions on the user pod.
+     * @param {boolean} enable
+     */
     togglePinTransitions: function(enable) {
       for (var i = 0; i < this.pods.length; ++i)
         this.pods[i].toggleTransitions(enable);
     },
 
+    /**
+     * Performs visual changes on the user pod if there is an error.
+     * @param {boolean} visible Whether to show or hide the display.
+     */
+    setFocusedPodErrorDisplay: function(visible) {
+      if (this.focusedPod_)
+        this.focusedPod_.setErrorDisplay(visible);
+    },
+
+    /**
+     * Shows or hides the pin keyboard for the current focused pod.
+     * @param {boolean} visible
+     */
     setFocusedPodPinVisibility: function(visible) {
       if (this.focusedPod_ && this.focusedPod_.user.showPin)
         this.focusedPod_.setPinVisibility(visible);
@@ -2975,9 +3027,9 @@ cr.define('login', function() {
 
       // Wrap this in a set timeout so the function is called after the pod is
       // finished transitioning so that we work with the final pod dimensions.
-      setTimeout(function(podrow) {
-        podrow.scrollFocusedPodIntoView();
-      }, 200, this);
+      setTimeout(function() {
+        this.scrollFocusedPodIntoView();
+      }.bind(this), 200);
     },
 
     /**