Add ChromeBrowserMainExtraParts for non main parts. (take 3)

content/shell/shell_content_browser_client.cc

Index: content/shell/shell_content_browser_client.cc
diff --git a/content/shell/shell_content_browser_client.cc b/content/shell/shell_content_browser_client.cc
index ec25de508038e56d588142335de81627fe14e95e..394af26a05b12618e5d60b8a1c43b9c359554613 100644
--- a/content/shell/shell_content_browser_client.cc
+++ b/content/shell/shell_content_browser_client.cc
@@ -28,10 +28,9 @@ ShellContentBrowserClient::ShellContentBrowserClient()
 ShellContentBrowserClient::~ShellContentBrowserClient() {
 }
 
-void ShellContentBrowserClient::CreateBrowserMainParts(
-    const content::MainFunctionParams& parameters,
-    std::vector<BrowserMainParts*>* parts_list) {
-  parts_list->push_back(new ShellBrowserMainParts(parameters));
+BrowserMainParts* ShellContentBrowserClient::CreateBrowserMainParts(
+    const content::MainFunctionParams& parameters) {
+  return new ShellBrowserMainParts(parameters);
 }
 
 RenderWidgetHostView* ShellContentBrowserClient::CreateViewForWidget(