Loading the Launcher with a Locked Profile launched UserManager.

chrome/browser/chrome_browser_main.h

Index: chrome/browser/chrome_browser_main.h
diff --git a/chrome/browser/chrome_browser_main.h b/chrome/browser/chrome_browser_main.h
index 65cbaa378ad7ad5f601582859a2d3cd3eb1d1ec8..aa9d6cc450e473c182a14fcaf3bdae9cb2386397 100644
--- a/chrome/browser/chrome_browser_main.h
+++ b/chrome/browser/chrome_browser_main.h
@@ -87,6 +87,9 @@ class ChromeBrowserMainParts : public content::BrowserMainParts {
   const base::CommandLine& parsed_command_line() const {
     return parsed_command_line_;
   }
+  const base::FilePath& user_data_dir() const {
+    return user_data_dir_;
+  }
 
   Profile* profile() { return profile_; }