Delay instantiating InputDeviceCapabilities until accessed.

third_party/WebKit/Source/core/events/UIEventWithKeyState.h

 /*
  * Copyright (C) 2001 Peter Kelly (pmk@post.com)
  * Copyright (C) 2001 Tobias Anton (anton@stud.fbi.fh-darmstadt.de)
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 58 matching lines @@
  protected:
   UIEventWithKeyState() : m_modifiers(0) {}
 
   UIEventWithKeyState(const AtomicString& type,
                       bool canBubble,
                       bool cancelable,
                       AbstractView*,
                       int detail,
                       PlatformEvent::Modifiers,
                       TimeTicks platformTimeStamp,
-                      InputDeviceCapabilities* sourceCapabilities = nullptr);
+                      const InputDeviceCapabilitiesValue& sourceCapabilities);
   UIEventWithKeyState(const AtomicString& type,
                       const EventModifierInit& initializer);
   void initModifiers(bool ctrlKey, bool altKey, bool shiftKey, bool metaKey);
 
   unsigned m_modifiers;
 
  private:
   static bool s_newTabModifierSetFromIsolatedWorld;
 };
 
 UIEventWithKeyState* findEventWithKeyState(Event*);
 
 }  // namespace blink
 
 #endif  // UIEventWithKeyState_h