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..9a9fae08eea5eea998faef958d0bc7d7e026d969 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 +16,19 @@ binding.registerCustomHook(function(bindingsAPI) {
     setIcon(details, callback, this.name, this.definition.parameters,
         'browser action');
   });
+
+  apiFunctions.setCustomCallback('openPopup',
+                                 function(name, request, response) {
+    if (chrome.runtime.lastError)
+      throw new Error(chrome.runtime.lastError.message);

[not at google - send to devlin, 2013/10/23 23:18:42]

don't throw an error here. chrome.runtime.lastError should just be set for the
callback. the code for this should look something like

if (!request.callback)
  return;

if (chrome.runtime.lastError) {
  request.callback();
  return;
}

[justinlin, 2013/10/24 00:01:38]

Ah thanks. https://codereview.chromium.org/32283005/. I thought API's can throw
an exception as well on error, but I think that's only for before the call when
things like input parameters are the wrong type. 

+
+    if (!request.callback)
+      return;
+
+    var views = getExtensionViews(-1, 'POPUP');
+    request.callback(views.length > 0 ? views[0] : null);
+    request.callback = null;
+  });
 });
 
 exports.binding = binding.generate();