Property "name" undefined in hashCode getter

[WieFel]

Describe the bug
File tinycolor.dart: name property is not defined but used in the getter hashCode, added in #16.

To Reproduce
Steps to reproduce the behavior:

1. Checkout master branch of this project.
2. Open in Android Studio or other IDE
3. See the error

Screenshots

Environment (please complete the following information)

• Flutter (Channel stable, 2.2.3, on Linux, locale en_GB.UTF-8)