[Password Manager] Add UMA signals to understand how often the password form submit navigate…

chrome/browser/password_manager/chrome_password_manager_client.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/password_manager/chrome_password_manager_client.h"
 
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/memory/singleton.h"
 #include "base/metrics/histogram.h"
@@ skipping 562 matching lines @@
 
   if (group_name == "DisallowSyncCredentialsForReauth") {
     autofill_sync_state_ = DISALLOW_SYNC_CREDENTIALS_FOR_REAUTH;
   } else if (group_name == "DisallowSyncCredentials") {
       autofill_sync_state_ = DISALLOW_SYNC_CREDENTIALS;
   } else {
     // Allow by default.
     autofill_sync_state_ = ALLOW_SYNC_CREDENTIALS;
   }
 }
+
+const GURL& ChromePasswordManagerClient::GetMainFrameURL() {
+  return web_contents()->GetVisibleURL();
+}