Move GeolocationClientMock.h out of platform/ into web/

Source/web/web.gypi

 {
   'variables': {
     'web_files': [
       'ApplicationCacheHost.cpp',
       'ApplicationCacheHostInternal.h',
       'AssertMatchingEnums.cpp',
       'AssociatedURLLoader.cpp',
       'AssociatedURLLoader.h',
       'BackForwardClientImpl.cpp',
       'BackForwardClientImpl.h',
@@ skipping 27 matching lines @@
       'ExternalPopupMenu.cpp',
       'ExternalPopupMenu.h',
       'FindInPageCoordinates.cpp',
       'FindInPageCoordinates.h',
       'FrameLoaderClientImpl.cpp',
       'FrameLoaderClientImpl.h',
       'FullscreenController.cpp',
       'FullscreenController.h',
       'GeolocationClientProxy.cpp',
       'GeolocationClientProxy.h',
+      'GeolocationClientMock.cpp',
+      'GeolocationClientMock.h',
       'GraphicsLayerFactoryChromium.cpp',
       'GraphicsLayerFactoryChromium.h',
       'IDBFactoryBackendProxy.cpp',
       'IDBFactoryBackendProxy.h',
       'InspectorClientImpl.cpp',
       'InspectorClientImpl.h',
       'InspectorFrontendClientImpl.cpp',
       'InspectorFrontendClientImpl.h',
       'LinkHighlight.cpp',
       'LinkHighlight.h',
@@ skipping 312 matching lines @@
         {
           'web_unittest_files': [
             'tests/KeyCodeConversionTestGtk.cpp',
             'tests/WebInputEventFactoryTestGtk.cpp',
           ],
         }
       ],
     ],
   },
 }