Merge from origin/emacs-26

fc5cae7 ; Fix ChangeLog typo.
e17a5e5 ; make change-history-commit
f205928 * etc/HISTORY: Cite Brinkoff on early history.
4e58ca8 Document internal use of 'above-suspended' z-group frame para...
4bd43b0 Increase max-lisp-eval-depth adjustment while in debugger (bu...
ab98352 Improve on last change in replace-buffer-contents
2f149c0 Fix a factual error in Introduction to Emacs Lisp
8ad50a3 ; * lisp/files.el (buffer-offer-save): Doc fix.  (Bug#32000)
c80f31f Minor improvements in documentation of imenu.el
8ebb683 Avoid errors with recentering in 'skeleton-insert'
e980a3c * src/lisp.h: Omit obsolete comment re bytecode stack.
eec71eb Speed up replace-buffer-contents
93c41ce Remove extra process call from vc-git-find-file-hook
7ea0873 ; Update some commentary
4a7f423 Speed up vc-git-dir-status-files
9134c84 Avoid compiler warning using coding.h

Conflicts:
	src/editfns.c

lisp/emacs-lisp/debug.el

@@ -349,6 +349,7 @@ That buffer should be current already."
                  (backtrace-frames 'debug)))
         (print-escape-newlines t)
         (print-escape-control-characters t)
+        ;; If you increase print-level, add more depth in call_debugger.
         (print-level 8)
         (print-length 50)
         (pos (point)))