Move to new file: Moving an import statement may break code

[ghost]

Code

See moveToNewFile_moveImport.ts.

[|import { a, b } from "m";
a;|]
b;

Expected behavior:

The import of b is kept in the original file since it's still needed.

Actual behavior:

The import is wholly removed from the old file, and an extra import is added to the new file for a even though it already has that.