aura: Add back XInputHierarchyChangedEventListener for aura and remove stubs.

chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.cc

Index: chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.cc
diff --git a/chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.cc b/chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.cc
index 1af7898ad6469d5bfb30baf63db964e48bce2942..bc39182de37655277b71d093977df93ca0475f6a 100644
--- a/chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.cc
+++ b/chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.cc
@@ -4,7 +4,6 @@
 
 #include "chrome/browser/chromeos/xinput_hierarchy_changed_event_listener.h"
 
-#include <gdk/gdkx.h>
 #include <X11/Xlib.h>
 #include <X11/extensions/XInput2.h>
 
@@ -76,12 +75,7 @@ XInputHierarchyChangedEventListener::XInputHierarchyChangedEventListener()
     : stopped_(false),
       xiopcode_(GetXInputOpCode()) {
   SelectXInputEvents();
-
-#if defined(TOUCH_UI) || !defined(TOOLKIT_USES_GTK)
-  MessageLoopForUI::current()->AddObserver(this);
-#else
-  gdk_window_add_filter(NULL, GdkEventFilter, this);
-#endif
+  Init();
 }
 
 XInputHierarchyChangedEventListener::~XInputHierarchyChangedEventListener() {
@@ -92,60 +86,21 @@ void XInputHierarchyChangedEventListener::Stop() {
   if (stopped_)
     return;
 
-#if defined(TOUCH_UI) || !defined(TOOLKIT_USES_GTK)
-  MessageLoopForUI::current()->RemoveObserver(this);
-#else
-  gdk_window_remove_filter(NULL, GdkEventFilter, this);
-#endif
+  StopImpl();
   stopped_ = true;
   xiopcode_ = -1;
 }
 
-#if defined(TOUCH_UI) || !defined(TOOLKIT_USES_GTK)
-base::EventStatus XInputHierarchyChangedEventListener::WillProcessEvent(
-    const base::NativeEvent& event) {
-  // There may be multiple listeners for the XI_HierarchyChanged event. So
-  // always return EVENT_CONTINUE to make sure all the listeners receive the
-  // event.
-  ProcessedXEvent(event);
-  return base::EVENT_CONTINUE;
-}
-
-void XInputHierarchyChangedEventListener::DidProcessEvent(
-    const base::NativeEvent& event) {
-}
-#else  // defined(TOUCH_UI) || !defined(TOOLKIT_USES_GTK)
-// static
-GdkFilterReturn XInputHierarchyChangedEventListener::GdkEventFilter(
-    GdkXEvent* gxevent, GdkEvent* gevent, gpointer data) {
-  XInputHierarchyChangedEventListener* listener =
-      static_cast<XInputHierarchyChangedEventListener*>(data);
-  XEvent* xevent = static_cast<XEvent*>(gxevent);
-
-  return listener->ProcessedXEvent(xevent) ? GDK_FILTER_REMOVE
-                                           : GDK_FILTER_CONTINUE;
-}
-#endif  // defined(TOUCH_UI) || !defined(TOOLKIT_USES_GTK)
-
 bool XInputHierarchyChangedEventListener::ProcessedXEvent(XEvent* xevent) {
   if ((xevent->xcookie.type != GenericEvent) ||
       (xevent->xcookie.extension != xiopcode_)) {
     return false;
   }
-#if !defined(TOUCH_UI)
-  if (!XGetEventData(xevent->xgeneric.display, &xevent->xcookie)) {
-    VLOG(1) << "XGetEventData failed";
-    return false;
-  }
-#endif
   XGenericEventCookie* cookie = &(xevent->xcookie);
   const bool should_consume = (cookie->evtype == XI_HierarchyChanged);
   if (should_consume)
     HandleHierarchyChangedEvent(static_cast<XIHierarchyEvent*>(cookie->data));
 
-#if !defined(TOUCH_UI)
-  XFreeEventData(xevent->xgeneric.display, cookie);
-#endif
   return should_consume;
 }