Extract a delegate interface from c/b/input_method to permit decoupling from c/b.

chrome/chrome_tests_unit.gypi

 # Copyright 2012 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.
 {
   'targets': [
     {
       # This target contains mocks and test utilities that don't belong in
       # production libraries but are used by more than one test executable.
       'target_name': 'test_support_common',
       'type': 'static_library',
@@ skipping 62 matching lines @@
         'browser/chromeos/contacts/contact_test_util.cc',
         'browser/chromeos/contacts/contact_test_util.h',
         'browser/chromeos/cros/mock_cert_library.cc',
         'browser/chromeos/cros/mock_cert_library.h',
         'browser/chromeos/cros/mock_cryptohome_library.cc',
         'browser/chromeos/cros/mock_cryptohome_library.h',
         'browser/chromeos/cros/mock_network_library.cc',
         'browser/chromeos/cros/mock_network_library.h',
         'browser/chromeos/input_method/mock_candidate_window_controller.cc',
         'browser/chromeos/input_method/mock_candidate_window_controller.h',
+        'browser/chromeos/input_method/mock_input_method_delegate.cc',
+        'browser/chromeos/input_method/mock_input_method_delegate.h',
         'browser/chromeos/input_method/mock_input_method_manager.cc',
         'browser/chromeos/input_method/mock_input_method_manager.h',
         'browser/chromeos/input_method/mock_xkeyboard.cc',
         'browser/chromeos/input_method/mock_xkeyboard.h',
         'browser/chromeos/login/mock_login_status_consumer.cc',
         'browser/chromeos/login/mock_login_status_consumer.h',
         'browser/chromeos/login/mock_login_utils.cc',
         'browser/chromeos/login/mock_login_utils.h',
         'browser/chromeos/login/mock_url_fetchers.cc',
         'browser/chromeos/login/mock_url_fetchers.h',
@@ skipping 2219 matching lines @@
             'unit_tests.isolate',
           ],
           'sources': [
             'unit_tests.isolate',
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }