Merged Interfaces with incompatible methods and properties should be an error #20826

TypeScript Version: 2.7.0-dev.201xxxxx

Code

interface Foo {
    bold(): string;
}

interface Foo {
    bold: string;
}

var x: Foo;

const j = x.bold;

Expected behavior:
j is type any, TS issues an error on both declarations of bold because their type doesn't match.

Actual behavior:
No error, j is type string.

Please note, the colors DT package (and one other package) relies on our current buggy behavior here and will need to be fixed.