[3.9.0-beta] Type gets incorrectly un-narrowed after ifs

[eamodio]

TypeScript Version: 3.9.0-dev.20200327

Search Terms:

Expected behavior:
No error

Actual behavior:
Error:

Property 'name' does not exist on type 'object | Function'.
  Property 'name' does not exist on type 'object'.(2339)

Related Issues:

Code

function foo(instance: Function | object) {
	if (typeof instance === 'function') {
		if (instance.prototype == null || instance.prototype.constructor == null) {
			return instance.name;
		}
	}
}

Output

"use strict";
function foo(instance) {
    if (typeof instance === 'function') {
        if (instance.prototype == null || instance.prototype.constructor == null) {
            return instance.name;
        }
    }
}

Compiler Options

{
  "compilerOptions": {
    "noImplicitAny": true,
    "strictNullChecks": true,
    "strictFunctionTypes": true,
    "strictPropertyInitialization": true,
    "strictBindCallApply": true,
    "noImplicitThis": true,
    "noImplicitReturns": true,
    "alwaysStrict": true,
    "esModuleInterop": true,
    "declaration": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "moduleResolution": 2,
    "target": "ES2017",
    "jsx": "React",
    "module": "ESNext"
  }
}

Playground Link: Provided

[ahejlsberg]

The logic in #32774 has logic to reset to the declared type in certain cases. In #37134 we removed all such logic from other narrowings. We should remove it here as well.