base: Do not allow MessagePumpObservers to consume events.

base/message_loop/message_pump_x11.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.
 
 #include "base/message_loop/message_pump_x11.h"
 
 #include <glib.h>
 #include <X11/X.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/XKBlib.h>
@@ skipping 235 matching lines @@
 
 void MessagePumpX11::ProcessXEvent(MessagePumpDispatcher* dispatcher,
                                    XEvent* xev) {
   CHECK(dispatcher);
   bool have_cookie = false;
   if (xev->type == GenericEvent &&
       XGetEventData(xev->xgeneric.display, &xev->xcookie)) {
     have_cookie = true;
   }
 
-  if (!WillProcessXEvent(xev)) {
-    uint32_t action = dispatcher->Dispatch(xev);
-    bool should_quit = (action & POST_DISPATCH_QUIT_LOOP);
-    if (dispatcher != this && (action & POST_DISPATCH_PERFORM_DEFAULT))
-      action = Dispatch(xev);
-    if ((action & POST_DISPATCH_QUIT_LOOP) || should_quit)
-      Quit();
-    DidProcessXEvent(xev);
-  }
+  WillProcessXEvent(xev);
+  uint32_t action = dispatcher->Dispatch(xev);
+  bool should_quit = (action & POST_DISPATCH_QUIT_LOOP);
+  if (dispatcher != this && (action & POST_DISPATCH_PERFORM_DEFAULT))
+    action = Dispatch(xev);
+  if ((action & POST_DISPATCH_QUIT_LOOP) || should_quit)
+    Quit();
+  DidProcessXEvent(xev);
 
   if (have_cookie)
     XFreeEventData(xev->xgeneric.display, &xev->xcookie);
 }
 
-bool MessagePumpX11::WillProcessXEvent(XEvent* xevent) {
-  if (!observers().might_have_observers())
-    return false;
-  ObserverListBase<MessagePumpObserver>::Iterator it(observers());
-  MessagePumpObserver* obs;
-  while ((obs = it.GetNext()) != NULL) {
-    if (obs->WillProcessEvent(xevent))
-      return true;
-  }
-  return false;
+void MessagePumpX11::WillProcessXEvent(XEvent* xevent) {
+  FOR_EACH_OBSERVER(MessagePumpObserver, observers(), WillProcessEvent(xevent));

[sky, 2014/04/03 15:43:21]

I would just inline this now.

[sadrul, 2014/04/03 16:22:50]

I have kept this in a separate function for now since for the short term, we
will need to call back into this from the event-source (see
https://codereview.chromium.org/219743002/diff/110001/ui/events/platform/x11/...).
Once we can remove that todo, we should be able to just remove this.

 }
 
 void MessagePumpX11::DidProcessXEvent(XEvent* xevent) {
   FOR_EACH_OBSERVER(MessagePumpObserver, observers(), DidProcessEvent(xevent));
 }
 
 MessagePumpDispatcher* MessagePumpX11::GetDispatcherForXEvent(
     const NativeEvent& xev) const {
   ::Window x_window = FindEventTarget(xev);
   DispatchersMap::const_iterator it = dispatchers_.find(x_window);
@@ skipping 15 matching lines @@
   if (FindEventTarget(xev) == x_root_window_) {
     FOR_EACH_OBSERVER(MessagePumpDispatcher, root_window_dispatchers_,
                       Dispatch(xev));
     return POST_DISPATCH_NONE;
   }
   MessagePumpDispatcher* dispatcher = GetDispatcherForXEvent(xev);
   return dispatcher ? dispatcher->Dispatch(xev) : POST_DISPATCH_NONE;
 }
 
 }  // namespace base