Adding JS and C++ handlers for events on new Welcome page.

chrome/browser/resources/welcome/welcome.html

Index: chrome/browser/resources/welcome/welcome.html
diff --git a/chrome/browser/resources/welcome/welcome.html b/chrome/browser/resources/welcome/welcome.html
index f3408af18ed21a9bfc0b9a2c905d41e6b85768d7..b3ceb000e18ef85dfd18813bafc1286497c2cbbe 100644
--- a/chrome/browser/resources/welcome/welcome.html
+++ b/chrome/browser/resources/welcome/welcome.html
@@ -10,7 +10,9 @@
   <link rel="stylesheet" href="chrome://resources/css/text_defaults_md.css">
   <link rel="stylesheet" href="chrome://welcome/welcome.css">
 
+  <script src="chrome://resources/js/cr.js"></script>
   <script src="chrome://resources/js/load_time_data.js"></script>
+  <script src="chrome://resources/js/util.js"></script>
   <script src="chrome://welcome/welcome.js"></script>
 
 </head>
@@ -31,8 +33,8 @@
     <div class="signin">
       <div class="signin-description">$i18n{descriptionText}</div>
       <div class="signin-buttons">
-        <paper-button class="action">$i18n{acceptText}</paper-button>
-        <a href="#" class="link">$i18n{declineText}</a>
+        <paper-button class="action" id="accept_button">$i18n{acceptText}</paper-button>

[anthonyvd, 2016/09/19 17:12:15]

nit: I *think* you should have dashes instead of underscores for id values.

+        <a href="#" class="link" id="decline_button">$i18n{declineText}</a>
       </div>
     </div>
   </div>