Enable copying long text to Chrome and pasting long text from Chrome

ui/base/x/x11_foreign_window_manager.h

+// 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.
+
+#ifndef UI_BASE_X_X11_FOREIGN_WINDOW_MANAGER_H_
+#define UI_BASE_X_X11_FOREIGN_WINDOW_MANAGER_H_
+
+#include <map>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "ui/base/ui_base_export.h"
+#include "ui/gfx/x/x11_types.h"
+
+// A process wide singleton for selecting events on X windows which were not
+// created by Chrome.
+template <typename T> struct DefaultSingletonTraits;
+
+namespace ui {
+
+// Manages the events that Chrome has selected on X windows which were not
+// created by Chrome. This class allows several clients to select events
+// on the same X window.
+class UI_BASE_EXPORT XForeignWindowManager {
+ public:
+  static XForeignWindowManager* GetInstance();
+
+  // Requests that events associated with |event_mask| on |xid| be reported to
+  // Chrome. Returns an id to use for canceling the request.
+  int RequestEvents(XID xid, long event_mask) WARN_UNUSED_RESULT;
+
+  // Cancels the request with |request_id|. Unless there is another request for
+  // events on the X window associated with |request_id|, this stops Chrome from
+  // getting events for the X window.
+  void CancelRequest(int request_id);
+
+  // Called by X11DesktopHandler when |xid| is destroyed.
+  void OnWindowDestroyed(XID xid);
+
+ private:
+  friend struct DefaultSingletonTraits<XForeignWindowManager>;
+
+  struct Request {
+    Request(int request_id, long entry_event_mask);
+    ~Request();
+
+    int request_id;
+    long event_mask;
+  };
+
+  XForeignWindowManager();
+  ~XForeignWindowManager();
+
+  // Updates which events are selected on |xid|.
+  void UpdateSelectedEvents(XID xid);
+
+  // The id of the next request.
+  int next_request_id_;
+
+  typedef std::vector<Request> RequestVector;
+  std::map<XID, RequestVector> request_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(XForeignWindowManager);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_X_X11_FOREIGN_WINDOW_MANAGER_H_