patch 8.0.1351: warning for unused variables building with MinGW

Problem:    Warning for unused variables building with MinGW.
Solution:   Change a few #ifdefs (suggested by John Marriott). Remove
            superfluous checks of FEAT_MBYTE.

patch 8.0.1350: cannot build with +eval and -multi_byte

Problem:    Cannot build with +eval and -multi_byte.
Solution:   Adjust #ifdefs. (John Marriott)  Always include the multi_byte
            feature when an input method feature is enabled.

patch 8.0.1349: options test fails when using Motif or GTK GUI

Problem:    Options test fails when using Motif or GTK GUI.
Solution:   Use "fixed" instead of "fixedsys" for Unix. Don't try "xxx" for
            guifonteset.  Don't set 'termencoding' to anything but "utf-8" for
            GTK.  Give an error if 'termencoding' can't be converted.

patch 8.0.1348: make testclean deletes script file on MS-Windows

Problem:    Make testclean deletes script file on MS-Windows.
Solution:   Rename file to avoid it starting with an "x".

patch 8.0.1347: MS-Windows: build broken by misplaced curly

Problem:    MS-Windows: build broken by misplaced curly.
Solution:   Move curly after #endif

patch 8.0.1346: crash when passing 50 char string to balloon_split()

Problem:    Crash when passing 50 char string to balloon_split().
Solution:   Fix off-by-one error.

patch 8.0.1345: race condition between stat() and open() for viminfo

Problem:    Race condition between stat() and open() for the viminfo temp
            file. (Simon Ruderich)
Solution:   use open() with O_EXCL to atomically check if the file exists.
            Don't try using a temp file, renaming it will fail anyway.

patch 8.0.1344: using 'imactivatefunc' in the GUI does not work

Problem:    Using 'imactivatefunc' in the GUI does not work.
Solution:   Do not use 'imactivatefunc' and 'imstatusfunc' in the GUI.

patch 8.0.1343: MS-Windows: does not show colored emojis

Problem:    MS-Windows: does not show colored emojis.
Solution:   Implement colored emojis. Improve drawing speed. Make 'taamode'
            work. (Taro Muraoka, Yasuhiro Matsumoto, Ken Takata, close vim#2375)

patch 8.0.1342: cannot build with Motif and multi-byte

Problem:    Cannot build with Motif and multi-byte. (Mohamed Boughaba)
Solution:   Use the right input method status flag. (closes vim#2374)