Merge from origin/emacs-26

Merge from origin/emacs-26

7efcdf7 (origin/emacs-26) Clarify completion text in the ELisp manual
30b0b0e Fix handling of abbreviated control command in gdb-mi.el
5cf282d Clarify documentation of functions reading character events
96281c5 Record :version for built-in variables while dumping
82160cf * src/process.c (connect_network_socket): Fix memory leak.  (...
6c616e4 * Makefile.in (appdatadir): Use the non-obsolete location "me...
9618e16 Better fix for bug#32550
30d94e4 Fix Bug#32550
57bcdc7 Don't call XGetGeometry for frames without outer X window (Bu...
82fc6b6 * lisp/calculator.el: Fix doc typo.
ddc7c64 Standardize calc bug reporting instructions

Conflicts:
	lisp/cus-start.el