MacViews: Add WidgetEventGenerator to abstract platform-specific event generation for tests.

ui/views/views.gyp

Index: ui/views/views.gyp
diff --git a/ui/views/views.gyp b/ui/views/views.gyp
index 7639936fcc01ab09ef7179692064fa3946a7f96d..4f5b983fddb29b8dfef453cbb87e0e39545722a6 100644
--- a/ui/views/views.gyp
+++ b/ui/views/views.gyp
@@ -629,6 +629,9 @@
         'test/views_test_helper_aura.h',
         'test/views_test_helper_mac.h',
         'test/views_test_helper_mac.mm',
+        'test/widget_event_generator.h',
+        'test/widget_event_generator_aura.cc',
+        'test/widget_event_generator_mac.mm',
         'test/widget_test.cc',
         'test/widget_test.h',
         'test/widget_test_aura.cc',
@@ -669,6 +672,7 @@
         '../compositor/compositor.gyp:compositor_test_support',
         '../events/events.gyp:events',
         '../events/events.gyp:events_base',
+        '../events/events.gyp:events_test_support',
         '../gfx/gfx.gyp:gfx',
         '../gfx/gfx.gyp:gfx_geometry',
         '../resources/ui_resources.gyp:ui_resources',
@@ -815,13 +819,11 @@
           'sources!': [
             'bubble/bubble_window_targeter_unittest.cc',
             'controls/button/custom_button_unittest.cc',
-            'controls/button/menu_button_unittest.cc',
             'controls/native/native_view_host_unittest.cc',
             'controls/menu/menu_controller_unittest.cc',
             'ime/input_method_bridge_unittest.cc',
             'focus/focus_manager_unittest.cc',
             'widget/window_reorderer_unittest.cc',
-            'widget/widget_unittest.cc',
           ]
         }],
       ],