Removes the objects in the range start inclusive to end exclusive.
The provide range, given by start and end, must be valid.
A range from start to end is valid if 0 <= start <= end <= len, where
len is this list's length. The range starts at start and has length
end - start. An empty range (with end == start) is valid.
Throws an UnsupportedError if this is a fixed-length list. In that case
the list is not modified.
Source
void removeRange(int start, int end) {
_checkRange(start, end);
callMethod('splice', [start, end - start]);
}