Remove more `textScaleFactor` references from flutter/flutter.  

- Some changes are related to label scaling: the padding EdgeInsets values of some chip subclasses scale linearly between predetermined "max" padding values and "min" padding values. Before they scale with the `textScaleFactor` scalar, now they scale with the font size and are still capped at the original "max" and "min" values.
- The rest of them are tests or size heuristics that depend on `textScaleFactor`, these are replaced by an effective text scale factor computed using a default font size (which is determined in a pretty random fashion, but it will only make a difference on Android 14+).

No API changes in this batch. There are still some references left that I intend to remove in a different batch that would introduce API changes.