Blend constructor Null safety

1. Flutter
2. blend
3. Blend
4. Blend constructor

Blend class

1. Constructors
2. Blend
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. toString
9. Operators
10. operator ==
11. Static methods
12. cam16Ucs
13. harmonize
14. hctHue