SI-6853 changed private method remove to be tail recursive.
Operations += and -= on mutable.ListMap rely on the private method remove to perform. This methods was implemented using recursion, but it was not tail recursive. When the ListMap got too big the += caused a StackOverflowError.
Merge pull request #1960 from ViniciusMiana/2.10.x

SI-6853 changed private method remove to be tail recursive.