Send early ShowPress on TapDown when page isn't scrollable/pinchable.

Source/core/page/ChromeClient.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple, Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 2012 Samsung Electronics. 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 249 matching lines @@
     // Notifies the client of a new popup widget.  The client should place
     // and size the widget with the given bounds, relative to the screen.
     // If handleExternal is true, then drawing and input handling for the
     // popup will be handled by the external embedder.
     virtual void popupOpened(PopupContainer* popupContainer, const IntRect& bounds,
                              bool handleExternal) = 0;
 
     // Notifies the client a popup was closed.
     virtual void popupClosed(PopupContainer* popupContainer) = 0;
 
+    virtual float minimumPageScaleFactor() const = 0;

[Rick Byers, 2014/02/14 21:27:53]

did aelias@ suggest exposing both of these?  I was expecting something more
specific to pinch being enabled (eg. how does this interact with browser zoom on
desktop which I believe uses page scale factor as well?).  But I defer to
aelias@ here.  This is probably OK too.

[bokan, 2014/02/18 19:59:57]

I think these should instead be isPinchZoomable() (maybe with better name). It's
not immediately clear that "pinch zoom disabled iff minimum == maximum" (i.e.
pinch code could check the user-scale=no setting without consulting min/max).
This would be more explicit.

+    virtual float maximumPageScaleFactor() const = 0;
+
 protected:
     virtual ~ChromeClient() { }
 };
 
 }
 #endif // ChromeClient_h