Update page action manifest parsing to match the new format.

chrome/browser/extensions/extension_process_manager.cc

Index: chrome/browser/extensions/extension_process_manager.cc
diff --git a/chrome/browser/extensions/extension_process_manager.cc b/chrome/browser/extensions/extension_process_manager.cc
index 9ae47a7e3b86f13e790e625b9b5feec22680f29e..e9bb7c49c090bbec6d4ab098ad85904e02dac9ab 100644
--- a/chrome/browser/extensions/extension_process_manager.cc
+++ b/chrome/browser/extensions/extension_process_manager.cc
@@ -130,11 +130,8 @@ void ExtensionProcessManager::RegisterExtensionProcess(
 
   std::vector<std::string> page_action_ids;
   Extension* extension = extension_service->GetExtensionById(extension_id);
-  for (ExtensionActionMap::const_iterator i =
-           extension->page_actions().begin();
-       i != extension->page_actions().end(); ++i) {
-    page_action_ids.push_back(i->first);
-  }
+  if (extension->page_action())
+    page_action_ids.push_back(extension->page_action()->id());
 
   RenderProcessHost* rph = RenderProcessHost::FromID(process_id);
   rph->Send(new ViewMsg_Extension_UpdatePageActions(extension_id,