Allow selecting region with mouse to move point to beginning

* etc/NEWS: Mention new user option
`mouse-select-region-move-to-beginning'.

* doc/emacs/frames.texi (Mouse Commands): Add cross-reference
to the following.
(Word and Line Mouse): Describe how double-clicking mouse-1 to
activate region and `mouse-select-region-move-to-beginning'
affect point.

* lisp/mouse.el (mouse-select-region-move-to-beginning): New defcustom.
(mouse-set-point): Use it.  (Bug#23478)

1 files changed, 7 insertions, 0 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 54b62f02ee3..5472dd84b77 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -56,6 +56,13 @@ affected by this, as SGI stopped supporting IRIX in December 2013.
 
 * Changes in Emacs 25.2
 
++++
+** The new user option 'mouse-select-region-move-to-beginning'
+controls the position of point when double-clicking mouse-1 on the end
+of a parenthetical grouping or string-delimiter: the default value nil
+keeps point at the end of the region, setting it to non-nil moves
+point to the beginning of the region.
+
 ---
 ** 'find-library-name' will now fall back on looking at 'load-history'
 to try to locate libraries that have been loaded with an explicit path