Merge "Rewrite multicharacter constant using constexpr"

class BitTube;

class IDisplayEventConnection;

// ----------------------------------------------------------------------------

static inline constexpr uint32_t fourcc(char c1, char c2, char c3, char c4) {

    return static_cast<uint32_t>(c1) << 24 |

        static_cast<uint32_t>(c2) << 16 |

        static_cast<uint32_t>(c3) << 8 |

        static_cast<uint32_t>(c4);

}

// ----------------------------------------------------------------------------

class DisplayEventReceiver {

public:

    enum {

        DISPLAY_EVENT_VSYNC = 'vsyn',

        DISPLAY_EVENT_HOTPLUG = 'plug'

        DISPLAY_EVENT_VSYNC = fourcc('v', 's', 'y', 'n'),

        DISPLAY_EVENT_HOTPLUG = fourcc('p', 'l', 'u', 'g'),

    };

    struct Event {