
Changes: - Remove 2<sup>nd</sup> person language from docs ([relevant style guideline](https://github.com/flutter/flutter/blob/master/docs/contributing/Style-guide-for-Flutter-repo.md#use-the-passive-voice-recommend-do-not-require-never-say-things-are-simple)) - Update a bunch of spots to be more explicit about `WidgetStateMouseCursor`. - `WidgetStateFoo` constructors now accurately describe what happens when used incorrectly. - Gave `WidgetStateProperty` a little section about equality checks.