Add PlatformWindow/Event related code for Ozone X11.

ui/events/platform/x11/x11_event_source_libevent.cc

-// Copyright 2014 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 "ui/events/platform/x11/x11_event_source.h"
-
-#include <X11/Xlib.h>
-
-#include "base/macros.h"
-#include "base/message_loop/message_loop.h"
-#include "base/message_loop/message_pump_libevent.h"
-
-namespace ui {
-
-namespace {
-
-class X11EventSourceLibevent : public X11EventSource,
-                               public base::MessagePumpLibevent::Watcher {
- public:
-  explicit X11EventSourceLibevent(XDisplay* display)
-      : X11EventSource(display),
-        initialized_(false) {
-    AddEventWatcher();
-  }
-
-  ~X11EventSourceLibevent() override {
-  }
-
- private:
-  void AddEventWatcher() {
-    if (initialized_)
-      return;
-    if (!base::MessageLoop::current())
-      return;
-
-    int fd = ConnectionNumber(display());
-    base::MessageLoopForUI::current()->WatchFileDescriptor(fd, true,
-        base::MessagePumpLibevent::WATCH_READ, &watcher_controller_, this);
-    initialized_ = true;
-  }
-
-  // PlatformEventSource:
-  void OnDispatcherListChanged() override {
-    AddEventWatcher();
-  }
-
-  // base::MessagePumpLibevent::Watcher:
-  void OnFileCanReadWithoutBlocking(int fd) override {
-    DispatchXEvents();
-  }
-
-  void OnFileCanWriteWithoutBlocking(int fd) override {
-    NOTREACHED();
-  }
-
-  base::MessagePumpLibevent::FileDescriptorWatcher watcher_controller_;
-  bool initialized_;
-
-  DISALLOW_COPY_AND_ASSIGN(X11EventSourceLibevent);
-};
-
-}  // namespace
-
-scoped_ptr<PlatformEventSource> PlatformEventSource::CreateDefault() {
-  return make_scoped_ptr(new X11EventSourceLibevent(gfx::GetXDisplay()));
-}
-
-}  // namespace ui