Removes all objects from this list that satisfy test.
An object o satisfies test if test(o) is true.
List<String> numbers = ['one', 'two', 'three', 'four'];
numbers.removeWhere((item) => item.length == 3);
numbers.join(', '); // 'three, four'
Throws an UnsupportedError if this is a fixed-length list.
Source
void removeWhere(bool test(E element)) {
throw new UnsupportedError("Cannot remove from immutable List.");
}