Update panel layout immediately after the user has finished resizing a panel.

ui/base/x/x11_util.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file defines utility functions for X11 (Linux only). This code has been
 // ported from XCB since we can't use XCB on Ubuntu while its 32-bit support
 // remains woefully incomplete.
 
 #include "ui/base/x/x11_util.h"
 
@@ skipping 445 matching lines @@
   black.red = black.green = black.blue = 0;
   Pixmap blank = XCreateBitmapFromData(xdisplay,
                                        DefaultRootWindow(xdisplay),
                                        nodata, 8, 8);
   invisible_cursor = XCreatePixmapCursor(xdisplay, blank, blank,
                                          &black, &black, 0, 0);
   XFreePixmap(xdisplay, blank);
   return invisible_cursor;
 }
 
+void SetUseOSWindowFrame(XID window, bool use_os_window_frame) {
+  // This data structure represents additional hints that we send to the window
+  // manager and has a direct lineage back to Motif, which defined this de facto
+  // standard. This struct doesn't seem 64-bit safe though, but it's what GDK
+  // does.
+  typedef struct {
+    unsigned long flags;
+    unsigned long functions;
+    unsigned long decorations;
+    long input_mode;
+    unsigned long status;
+  } MotifWmHints;
+
+  MotifWmHints motif_hints;
+  memset(&motif_hints, 0, sizeof(motif_hints));
+  // Signals that the reader of the _MOTIF_WM_HINTS property should pay
+  // attention to the value of |decorations|.
+  motif_hints.flags = (1L << 1);
+  motif_hints.decorations = use_os_window_frame ? 1 : 0;
+
+  ::Atom hint_atom = GetAtom("_MOTIF_WM_HINTS");
+  XChangeProperty(gfx::GetXDisplay(),
+                  window,
+                  hint_atom,
+                  hint_atom,
+                  32,
+                  PropModeReplace,
+                  reinterpret_cast<unsigned char*>(&motif_hints),
+                  sizeof(MotifWmHints)/sizeof(long));
+}
+
 bool IsShapeExtensionAvailable() {
   int dummy;
   static bool is_shape_available =
       XShapeQueryExtension(gfx::GetXDisplay(), &dummy, &dummy);
   return is_shape_available;
 }
 
 XID GetX11RootWindow() {
   return DefaultRootWindow(gfx::GetXDisplay());
 }
@@ skipping 902 matching lines @@
       << "request_code " << static_cast<int>(error_event.request_code) << ", "
       << "minor_code " << static_cast<int>(error_event.minor_code)
       << " (" << request_str << ")";
 }
 
 // ----------------------------------------------------------------------------
 // End of x11_util_internal.h
 
 
 }  // namespace ui