Implement initial chrome.browserAction.openPopup API.

chrome/renderer/resources/extensions/browser_action_custom_bindings.js

Index: chrome/renderer/resources/extensions/browser_action_custom_bindings.js
diff --git a/chrome/renderer/resources/extensions/browser_action_custom_bindings.js b/chrome/renderer/resources/extensions/browser_action_custom_bindings.js
index d90ab18235c3e7ac53f9429e0b8c9edc1c44ffa8..97720c560e8ccbdbcdbf46aed2ea99f25111b19e 100644
--- a/chrome/renderer/resources/extensions/browser_action_custom_bindings.js
+++ b/chrome/renderer/resources/extensions/browser_action_custom_bindings.js
@@ -7,6 +7,7 @@
 var binding = require('binding').Binding.create('browserAction');
 
 var setIcon = require('setIcon').setIcon;
+var getExtensionViews = requireNative('extension').GetExtensionViews;
 
 binding.registerCustomHook(function(bindingsAPI) {
   var apiFunctions = bindingsAPI.apiFunctions;
@@ -15,6 +16,16 @@ binding.registerCustomHook(function(bindingsAPI) {
     setIcon(details, callback, this.name, this.definition.parameters,
         'browser action');
   });
+
+  apiFunctions.setCustomCallback('openPopup',
+                                 function(name, request, response) {
+    if (!request.callback)
+      return;
+
+    var views = getExtensionViews(-1, 'POPUP');
+    request.callback(views.length > 0 ? views[0] : null);
+    request.callback = null;
+  });
 });
 
 exports.binding = binding.generate();