master 0b94669c14: Handle GraphicsExpose events on scroll bars

[Po Lu]

branch: master
commit 0b94669c14ad78c82f47adb4fb376ce48f5fe7e3
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Handle GraphicsExpose events on scroll bars
    
    * src/xterm.c (x_scroll_bar_expose): Handle GraphicsExpose
    events.
    (handle_one_xevent): Give graphics exposures to scroll bars.
---
 src/xterm.c | 31 +++++++++++++++++++++++++++----
 1 file changed, 27 insertions(+), 4 deletions(-)

diff --git a/src/xterm.c b/src/xterm.c
index 367e69fb95..90182a89f1 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -13143,6 +13143,22 @@ x_scroll_bar_expose (struct scroll_bar *bar, const 
XEvent *event)
 #else
   Drawable w = bar->x_drawable;
 #endif
+  int x, y, width, height;
+
+  if (event->type == Expose)
+    {
+      x = event->xexpose.x;
+      y = event->xexpose.y;
+      width = event->xexpose.width;
+      height = event->xexpose.height;
+    }
+  else
+    {
+      x = event->xgraphicsexpose.x;
+      y = event->xgraphicsexpose.y;
+      width = event->xgraphicsexpose.width;
+      height = event->xgraphicsexpose.height;
+    }
 
   struct frame *f = XFRAME (WINDOW_FRAME (XWINDOW (bar->window)));
   GC gc = f->output_data.x->normal_gc;
@@ -13161,10 +13177,7 @@ x_scroll_bar_expose (struct scroll_bar *bar, const 
XEvent *event)
 
       XFillRectangle (FRAME_X_DISPLAY (f),
                      bar->x_drawable,
-                     gc, event->xexpose.x,
-                     event->xexpose.y,
-                     event->xexpose.width,
-                     event->xexpose.height);
+                     gc, x, y, width, height);
 
       XSetForeground (FRAME_X_DISPLAY (f), gc,
                      FRAME_FOREGROUND_PIXEL (f));
@@ -14835,6 +14848,16 @@ handle_one_xevent (struct x_display_info *dpyinfo,
          show_back_buffer (f);
 #endif
         }
+#ifndef USE_TOOLKIT_SCROLL_BARS
+      struct scroll_bar *bar
+       = x_window_to_scroll_bar (dpyinfo->display,
+                                 /* Hopefully this is just a window,
+                                    not the back buffer.  */
+                                 event->xgraphicsexpose.drawable, 2);
+
+      if (bar)
+       x_scroll_bar_expose (bar, event);
+#endif
 #ifdef USE_X_TOOLKIT
       else
         goto OTHER;