Unified icon-buttons used in the new GAIA flow.

chrome/browser/resources/chromeos/login/screen_gaia_signin.js

Index: chrome/browser/resources/chromeos/login/screen_gaia_signin.js
diff --git a/chrome/browser/resources/chromeos/login/screen_gaia_signin.js b/chrome/browser/resources/chromeos/login/screen_gaia_signin.js
index e05e866219a63a6d5a780bb322074f8b6794fecf..8a8ba601c339f4d49b1955bd83af44add4082930 100644
--- a/chrome/browser/resources/chromeos/login/screen_gaia_signin.js
+++ b/chrome/browser/resources/chromeos/login/screen_gaia_signin.js
@@ -179,20 +179,12 @@ login.createScreen('GaiaSigninScreen', 'gaia-signin', function() {
         e.preventDefault();
       });
 
-      $('back-button-item').addEventListener('mousedown', function(e) {
-        e.preventDefault();
-      });
-
       $('back-button-item').addEventListener('click', function(e) {
         $('back-button-item').hidden = true;
         $('signin-frame').back();
         e.preventDefault();
       });
 
-      $('close-button-item').addEventListener('mousedown', function(e) {
-        e.preventDefault();
-      });
-
       $('close-button-item').addEventListener('click', function(e) {
         this.cancel();
         e.preventDefault();