fixAddMissingMember should create a constructor if not present

TypeScript Version: 2.7.0-dev.20171129

Code

a.js

class C {
    m() {
        this.x;
    }
}

Expected behavior:

Can fix the error by creating a constructor.

Actual behavior:

No codefix unless I manually add a constructor.

[mhegazy]

one issue here is creating a constructor to just get the type is a bit of an overkill.. it gets more interesting when you have a base class, now you have to create a forwarding constructor, ideally with the same number and names of parameters..

one alternative here is for us to support @property or @member on a class a a source of property declaration. #15715 tracks a similar scenario