X message pump: Remove the GDK window event filter.

This should fix some crashes that end up calling the event filter of a
destroyed message pump.

BUG=none
TEST=some randomly failing unit tests (e.g.  SessionServiceTest.GetCurrentSession)

Review URL: http://codereview.chromium.org/7031057

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@86672 0039d316-1c4b-4281-b951-d872f2087c98

base/message_pump_glib_x.cc

@@ -43,6 +43,11 @@ MessagePumpGlibX::MessagePumpGlibX() : base::MessagePumpForUI(),
 }
 
 MessagePumpGlibX::~MessagePumpGlibX() {
+  gdk_window_remove_filter(NULL, &GdkEventFilter, this);
+
+  // It is not necessary to reset the GDK event handler using
+  // gdk_event_handler_set since it's done in the destructor for
+  // MessagePumpForUI.
 }
 
 bool MessagePumpGlibX::ShouldCaptureXEvent(XEvent* xev) {