master 6b71b80fdc: Fix odd scrolling bugs on LessTif

[Po Lu]

branch: master
commit 6b71b80fdcf32aed5191898e7339ffb9dcd29005
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Fix odd scrolling bugs on LessTif
    
    * src/xterm.c (handle_one_xevent): Give emulated button events
    to Motif.
---
 src/xterm.c | 29 ++++++++++++++++++++---------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/src/xterm.c b/src/xterm.c
index f5ce42fc27..3f69300417 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -12035,17 +12035,13 @@ handle_one_xevent (struct x_display_info *dpyinfo,
              struct xwidget_view *xvw;
 #endif
 
-#ifdef HAVE_XINPUT2_1
-             /* Ignore emulated scroll events when XI2 native
-                scroll events are present.  */
-             if (xev->flags & XIPointerEmulated)
-               {
-                 *finish = X_EVENT_DROP;
-                 goto XI_OTHER;
-               }
+#ifdef USE_MOTIF
+#ifdef USE_TOOLKIT_SCROLL_BARS
+             struct scroll_bar *bar
+               = x_window_to_scroll_bar (dpyinfo->display,
+                                         xev->event, 2);
 #endif
 
-#ifdef USE_MOTIF
              use_copy = true;
              copy.xbutton.type = (xev->evtype == XI_ButtonPress
                                   ? ButtonPress : ButtonRelease);
@@ -12075,6 +12071,21 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                }
 #endif
 
+#ifdef HAVE_XINPUT2_1
+             /* Ignore emulated scroll events when XI2 native
+                scroll events are present.  */
+             if (xev->flags & XIPointerEmulated)
+               {
+#if !defined USE_MOTIF || !defined USE_TOOLKIT_SCROLL_BARS
+                 *finish = X_EVENT_DROP;
+#else
+                 if (bar)
+                   *finish = X_EVENT_DROP;
+#endif
+                 goto XI_OTHER;
+               }
+#endif
+
              if (xev->evtype == XI_ButtonPress)
                x_display_set_last_user_time (dpyinfo, xev->time);