Remove custom signatures from V8 bindings

Remove custom signatures from V8 bindings

- Previously custom signatures were specified on methods that have parameters whose type is a DOM object. For example:

  void foo(bool a, bool b, Node node);  // This method has a custom signature because Node is a DOM object.

- Custom signatures were used by V8 to validate the parameter type when the method is called back. However, it is a responsibility of (not V8 but) V8 binding to validate the parameter type. In fact, V8 binding already generates code for the validation. For example:

  Node* node = V8Node::hasInstance(args[2]) ? V8Node::toNative(args[2]) : 0;

- Thus, custom signatures are unnecessary. This CL removes the custom signatures completely.

- The only thing we have to be careful about is DOMWindow. Because DOMWindow has a hidden prototype chain, we cannot validate the parameter type just by checking V8Window::hasInstance(). Thus this CL adds toNativeDOMWindow() that looks up the prototype chain and finds an instance on the hidden prototype chain.

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=164407

[haraken, 2013-12-29 06:21:19]

PTAL

[kouhei (in TOK), 2014-01-01 01:00:00]

lgtm

[commit-bot: I haz the power, 2014-01-01 02:31:19]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/haraken@chromium.org/109473008/1

[commit-bot: I haz the power, 2014-01-01 02:37:58]

Change committed as 164407