Add basic PointerEvent support in NewEventHandler

sky/engine/core/events/PointerEvent.h

Index: sky/engine/core/events/PointerEvent.h
diff --git a/sky/engine/core/events/PointerEvent.h b/sky/engine/core/events/PointerEvent.h
index 5c2c0d41213257eacf8e96a0547ebcfb7efcb0db..86dbd438cead2cccebc77b72b40a561e1447a1bc 100644
--- a/sky/engine/core/events/PointerEvent.h
+++ b/sky/engine/core/events/PointerEvent.h
@@ -77,6 +77,8 @@ public:
     double orientation() const { return m_orientation; }
     double tilt() const { return m_tilt; }
 
+    void setPrimary(bool primary) { m_primary = primary; }

[esprehn, 2015/01/21 02:47:51]

Does this change dynamically? What happens if two events claim they're the
primary?

[abarth-chromium, 2015/01/21 07:03:26]

Currently everything is marked as primary.  It's something that will be computed
by the EventHandler.  I can move it to the constructor if you like.
That can happen if they're being captured by different nodes.  For example, if
you have two touches on two separate scroll views, they both scroll
independently because each touch is primary for each view.  If you put a third
finger down in one of the views, it will become secondary in that view and can
be used for something else (e.g., pinching).

[abarth-chromium, 2015/01/23 02:25:09]

I removed this for now.  When we have more of this system implemented, we can
add it back.

+
 private:
     PointerEvent();
     explicit PointerEvent(const WebPointerEvent& event);