Update charted to 0.4.8 and roll

packages/quiver_iterables/lib/src/range.dart

-// Copyright 2013 Google Inc. All Rights Reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-part of quiver.iterables;
-
-/// Returns an [Iterable] sequence of [num]s.
-///
-/// If only one argument is provided, [start_or_stop] is the upper bound for the
-/// sequence. If two or more arguments are provided, [stop] is the upper bound.
-///
-/// The sequence starts at 0 if one argument is provided, or [start_or_stop] if
-/// two or more arguments are provided. The sequence increments by 1, or [step]
-/// if provided. [step] can be negative, in which case the sequence counts down
-/// from the starting point and [stop] must be less than the starting point so
-/// that it becomes the lower bound.
-Iterable<num> range(num start_or_stop, [num stop, num step]) {
-  var start = (stop == null) ? 0 : start_or_stop;
-  stop = (stop == null) ? start_or_stop : stop;
-  step = (step == null) ? 1 : step;
-  if (step == 0) {
-    throw new ArgumentError("step cannot be 0");
-  }
-  if ((step > 0) && (stop < start)) {
-    throw new ArgumentError("if step is positive,"
-        " stop must be greater than start");
-  }
-  if ((step < 0) && (stop > start)) {
-    throw new ArgumentError("if step is negative,"
-        " stop must be less than start");
-  }
-  return _range(start, stop, step);
-}
-
-Iterable<num> _range(num start, num stop, num step) sync* {
-  while (step < 0 ? start > stop : start < stop) {
-    yield start;
-    start += step;
-  }
-}