[AC21.5] Cleaning out old work #3: don't clear unchanged toolbars

APPROVE COMMIT 21.5

>From Jeff Sparkes, another ancient improvement.  This actually helps
on my Mac locally, at least in a debug config running under lldb.  I'm
sure it makes a perceptible difference if running over the Internet.

diff -U0 -r 822430f873bc -r aa31767a919f src/ChangeLog
--- a/src/ChangeLog	Mon Jan 04 12:16:28 2016 +0900
+++ b/src/ChangeLog	Thu Jan 01 16:27:23 2015 -0500
@@ -0,0 +1,5 @@
+2015-01-01  Jeff Sparkes  <[email protected]>
+
+	* toolbar.c (update_frame_toolbars_geometry): Only clear the
+	frame's toolbar if the frame size has changed.
+
diff -r 822430f873bc -r aa31767a919f src/toolbar.c
--- a/src/toolbar.c	Mon Jan 04 12:16:28 2016 +0900
+++ b/src/toolbar.c	Thu Jan 01 16:27:23 2015 -0500
@@ -798,13 +798,12 @@
 				   &width, &height);
 	  internal_set_frame_size (f, width, height, 0);
 	  MARK_FRAME_LAYOUT_CHANGED (f);
+
+          /* Clear the previous toolbar locations. If we do it later
+             (after redisplay) we end up clearing what we have just
+             displayed. */
+          MAYBE_DEVMETH (d, clear_frame_toolbars, (f));
 	}
-      
-      /* Clear the previous toolbar locations. If we do it later
-	 (after redisplay) we end up clearing what we have just
-	 displayed. */
-      MAYBE_DEVMETH (d, clear_frame_toolbars, (f));
-
     }
 }