Use XGrabPointer instead of XChangeActivatePointerGrab() to change the cursor during a pointer grab

ui/views/widget/desktop_aura/x11_pointer_grab.cc

Index: ui/views/widget/desktop_aura/x11_pointer_grab.cc
diff --git a/ui/views/widget/desktop_aura/x11_pointer_grab.cc b/ui/views/widget/desktop_aura/x11_pointer_grab.cc
new file mode 100644
index 0000000000000000000000000000000000000000..13541599684428769595749d177177207183f77d
--- /dev/null
+++ b/ui/views/widget/desktop_aura/x11_pointer_grab.cc
@@ -0,0 +1,44 @@
+// Copyright 2015 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.
+
+#include "base/logging.h"
+#include "ui/views/widget/desktop_aura/x11_pointer_grab.h"
+
+#include <X11/Xlib.h>
+
+namespace views {
+
+namespace {
+
+// The grab window. None if there are no active pointer grabs.
+XID g_grab_window = None;
+
+// The "owner events" parameter used to grab the pointer.
+bool g_owner_events = false;
+
+}  // namespace
+
+int GrabPointer(XID window, bool owner_events, ::Cursor cursor) {
+  int event_mask = PointerMotionMask | ButtonReleaseMask | ButtonPressMask;
+  int result = XGrabPointer(gfx::GetXDisplay(), window, owner_events,
+                            event_mask, GrabModeAsync, GrabModeAsync, None,
+                            cursor, CurrentTime);
+  if (result == GrabSuccess) {
+    g_grab_window = window;
+    g_owner_events = owner_events;
+  }
+  return result;
+}
+
+void ChangeActivePointerGrabCursor(::Cursor cursor) {
+  DCHECK(g_grab_window != None);
+  GrabPointer(g_grab_window, g_owner_events, cursor);
+}
+
+void UngrabPointer() {
+  g_grab_window = None;
+  XUngrabPointer(gfx::GetXDisplay(), CurrentTime);
+}
+
+}  // namespace views