wip: Second crack at implementing the touch exploration mode.

ui/events/event_source.h

 // Copyright 2013 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_EVENTS_EVENT_SOURCE_H_
 #define UI_EVENTS_EVENT_SOURCE_H_
 
 #include <vector>
 
 #include "ui/events/event_dispatcher.h"
@@ skipping 18 matching lines @@
   // EventProcessor. The rewriter must be explicitly removed from the
   // EventSource before the rewriter is destroyed. The EventSource
   // does not take ownership of the rewriter.
   void AddEventRewriter(EventRewriter* rewriter);
   void RemoveEventRewriter(EventRewriter* rewriter);
 
  protected:
   EventDispatchDetails SendEventToProcessor(Event* event);
 
  private:
+  friend class EventSourceTestApi;
+
   typedef std::vector<EventRewriter*> EventRewriterList;
   EventDispatchDetails DeliverEventToProcessor(Event* event);
   EventRewriterList rewriter_list_;
   DISALLOW_COPY_AND_ASSIGN(EventSource);
 };
 
 }  // namespace ui
 
 #endif // UI_EVENTS_EVENT_SOURCE_H_