Forward mouse down node information to WebWidgetClient

Source/core/page/ChromeClient.h

Index: Source/core/page/ChromeClient.h
diff --git a/Source/core/page/ChromeClient.h b/Source/core/page/ChromeClient.h
index 85d7605910c7d8d9a7a483ea5759a63b15ef0a0e..ef416413d80f697e1eeeb66aabd393af355043d9 100644
--- a/Source/core/page/ChromeClient.h
+++ b/Source/core/page/ChromeClient.h
@@ -239,6 +239,8 @@ public:
 
     virtual void showUnhandledTapUIIfNeeded(IntPoint, Node*, bool) { }
 
+    virtual void onClickInput(Node*) { }

[please use gerrit instead, 2015/06/17 20:07:08]

Should this be called "onClickNode(Node*)" instead? I don't think it's
guaranteed to be an input field.

[Yufeng Shen (Slow to review), 2015/06/17 20:12:57]

oh, I think the name actually means the click is an "input event", not meaning
the Node is an "input" node. And later on we might want to 
pass more information out other than the Node*.

Does that make sense ?

[please use gerrit instead, 2015/06/17 20:58:05]

Sure.

+
     virtual void didUpdateTopControls() const { }
 
     virtual void registerPopupOpeningObserver(PopupOpeningObserver*) = 0;