Evaluate function declarations in catch statements properly

[robertsipka]

It is not a proper solution, however it is working. The createBinding function is not called for the GlobalEnvironment record in this test case (issue 26). I will investigate it why.

Fixes #26.

[robertsipka]

The following code caused the assert:

try { 
    throw ReferenceError('');
} catch ( x ) { 
    eval ( "function arguments (){};" );
}

The arguments is an array-like object which is accessible inside functions that contains the values of the arguments passed to that function.
When the ScriptParser computed the variables for the interpreted code block it erased the arguments identifier because it assumed that the eval code is part of a function.

This was not a problem if we ran the code inside a function:

function foo() {
    try { 
        throw ReferenceError('');
    } catch ( x ) { 
        eval ( "function arguments (){};" );
    }
}

However the arguments was also erased here, the engine created an arguments object for the function, so it appears again within the identifiers and we can overwrite it inside the eval code.

[akosthekiss]

It'd be great if this PR could wait for #41 so that the failure-inducing test case could be added to the regression test suite.

[ksh8281]

LGTM

[yichoi]

LGTM

[akosthekiss]

Well, @robertsipka , could you please open a separate PR to add the test case to the regression suite that hasn't get landed here?