Merge "Add color aspects keys" am: 8ecc7c19

        { "date", METADATA_KEY_DATE },

        { "width", METADATA_KEY_VIDEO_WIDTH },

        { "height", METADATA_KEY_VIDEO_HEIGHT },

        { "colorstandard", METADATA_KEY_COLOR_STANDARD },

        { "colortransfer", METADATA_KEY_COLOR_TRANSFER },

        { "colorrange", METADATA_KEY_COLOR_RANGE },

    };

    static const size_t kNumEntries = sizeof(kKeyMap) / sizeof(kKeyMap[0]);