Abstract WebContentsObserver from Autofill shared code

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 251 matching lines @@
         'test/ppapi/ppapi_test.h',
 
         # TODO(joi): Move to //components/components.gypi once
         # remaining dependencies back to //chrome are eliminated.
         '../components/autofill/browser/android/test_auxiliary_profile_loader_android.cc',
         '../components/autofill/browser/android/test_auxiliary_profile_loader_android.h',
         '../components/autofill/browser/autofill_common_test.cc',
         '../components/autofill/browser/autofill_common_test.h',
         '../components/autofill/browser/data_driven_test.cc',
         '../components/autofill/browser/data_driven_test.h',
+        '../components/autofill/browser/test_autofill_driver.cc',
+        '../components/autofill/browser/test_autofill_driver.h',
         '../components/autofill/browser/test_autofill_external_delegate.cc',
         '../components/autofill/browser/test_autofill_external_delegate.h',
         '../components/autofill/browser/test_autofill_manager_delegate.cc',
         '../components/autofill/browser/test_autofill_manager_delegate.h',
         '../components/autofill/browser/test_personal_data_manager.cc',
         '../components/autofill/browser/test_personal_data_manager.h',
 
         '../ui/gfx/image/image_unittest_util.h',
         '../ui/gfx/image/image_unittest_util.cc',
         '../webkit/browser/quota/mock_quota_manager.cc',
@@ skipping 2283 matching lines @@
               # more details.
               'DebugInformationFormat': '3',
               'ProgramDataBaseFileName': '<(PRODUCT_DIR)/unit_tests.exe.pdb',
             },
           },
         },
       ],
     }],
   ],  # 'conditions'
 }