Erroneous type narrowing in try / catch / finally with strictNullChecks

[davidni]

TypeScript Version: 2.4.1

Code
Compile with strictNullChecks = true
Playground link: here (make sure to enable strictNullChecks)

class A {
    a: string;
}

let foo: A | undefined = void 0;
try {
    foo = new A();
    throw new Error();
} catch (e) {
    if (foo) {
        foo.a; // ERROR: Property 'a' does not exist on type 'never'.
    }
}
finally {
    if (foo) {
        foo.a; // ERROR: Property 'a' does not exist on type 'never'.
    }
}

Expected behavior:
Should compile without errors

Actual behavior:
Compilation fails at the indicated lines. Control flow analysis assumes that foo is of type undefined as it enters the try / catch / finally block, and is unable to detect that foo will actually be of type A in both the catch and finally blocks.

Likely related to #15835 and #18478

[mhegazy]

Duplicate of #18478

[mhegazy]

Automatically closing this issue for housekeeping purposes. The issue labels indicate that it is unactionable at the moment or has already been addressed.