mshtml/tests: Fix return value of ActiveScript_SetScriptState.

[Jacek Caban]

Hi Gerald,

On 5/2/10 9:16 PM, Gerald Pfeifer wrote:
> IActiveScriptSite_OnStateChange is described to return S_OK upon
> success, so instead of ignoring its return value and unconditionally
> returning S_OK it strikes me that we should return its result instead.
>    

In this case returning S_OK is fine, but there is missing test for 
OnStateChange return value.

Jacek