Roll Observatory packages and add a roll script

quiver/lib/testing/src/time/time.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.testing.time;
-
-/**
- * Returns the current test time in microseconds.
- */
-typedef int Now();
-
-/**
- * A [Stopwatch] implementation that gets the current time in microseconds
- * via a user-supplied function.
- */
-class FakeStopwatch implements Stopwatch {
-  Now _now;
-  int frequency;
-  int _start;
-  int _stop;
-
-  FakeStopwatch(int now(), int this.frequency)
-      : _now = now,
-        _start = null,
-        _stop = null;
-
-  void start() {
-    if (isRunning) return;
-    if (_start == null) {
-      _start = _now();
-    } else {
-      _start = _now() - (_stop - _start);
-      _stop = null;
-    }
-  }
-
-  void stop() {
-    if (!isRunning) return;
-    _stop = _now();
-  }
-
-  void reset() {
-    if (_start == null) return;
-    _start = _now();
-    if (_stop != null) {
-      _stop = _start;
-    }
-  }
-
-  int get elapsedTicks {
-    if (_start == null) {
-      return 0;
-    }
-    return (_stop == null) ? (_now() - _start) : (_stop - _start);
-  }
-
-  Duration get elapsed => new Duration(microseconds: elapsedMicroseconds);
-
-  int get elapsedMicroseconds => (elapsedTicks * 1000000) ~/ frequency;
-
-  int get elapsedMilliseconds => (elapsedTicks * 1000) ~/ frequency;
-
-  bool get isRunning => _start != null && _stop == null;
-}