MiddleButtonDown  511 Source/web/WebInputEventConversion.cpp             modifiers |= WebInputEvent::MiddleButtonDown;
MiddleButtonDown  113 Source/web/WebInputEventFactoryGtk.cpp         modifiers |= WebInputEvent::MiddleButtonDown;
MiddleButtonDown  344 Source/web/WebInputEventFactoryWin.cpp         result.modifiers |= WebInputEvent::MiddleButtonDown;
MiddleButtonDown  442 Source/web/WebInputEventFactoryWin.cpp         result.modifiers |= WebInputEvent::MiddleButtonDown;