Break up common_custom_types.mojom.

chrome/common/importer/profile_import.mojom

 // Copyright 2016 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.
 
 module chrome.mojom;
 
 import "components/autofill/content/common/autofill_types.mojom";
-import "mojo/common/common_custom_types.mojom";
+import "mojo/common/string16.mojom";
+import "mojo/common/values.mojom";
 import "url/mojo/url.mojom";
 
 [Native]
 struct ImportedBookmarkEntry;
 
 [Native]
 struct ImporterAutofillFormDataEntry;
 
 [Native]
 struct SearchEngineInfo;
@@ skipping 56 matching lines @@
       uint16 items,
       mojo.common.mojom.DictionaryValue localized_strings,
       ProfileImportObserver observer);
 
   // Stop the importer.
   CancelImport();
 
   // Tell the importer that we're done with one item.
   ReportImportItemFinished(ImportItem item);
 };