[PATH] Honor $INSIDE_EMACS, not only $EMACS.

[Eli Zaretskii <eliz@gnu.org>]

Lately Emacs switched from defining $EMACS to $INSIDE_EMACS, when it
runs subprocesses, so GDB needs to follow suit to disable paging.

OK to commit the below?

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 66f6dd6..63a217f 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,9 @@
+2015-10-29  Eli Zaretskii  <eliz@gnu.org>
+
+	* utils.c (init_page_info): Disable paging if INSIDE_EMACS is set
+	in the environment.  Emacs 25 and later uses that variable instead
+	of EMACS.
+
 2015-10-29  Pedro Alves  <palves@redhat.com>
 
 	* common/common-exceptions.c (exception_none): Add cast.
diff --git a/gdb/utils.c b/gdb/utils.c
index 255aee8..968889c 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -1677,8 +1677,8 @@ init_page_info (void)
          Only try to use tgetnum function if rl_get_screen_size
          did not return a useful value. */
       if (((rows <= 0) && (tgetnum ("li") < 0))
-	/* Also disable paging if inside EMACS.  */
-	  || getenv ("EMACS"))
+	/* Also disable paging if inside Emacs.  */
+	  || getenv ("EMACS") || getenv ("INSIDE_EMACS"))
 	{
 	  /* The number of lines per page is not mentioned in the terminal
 	     description or EMACS evironment variable is set.  This probably