M143+ immutable SkPath breakage

[HinTak]

In m143, there is a switch to make SkPath immutable - all path editing methods are gone. (One is supposed to make new SkPath's, rather than modify existing ones). This is controlled by
SK_HIDE_PATH_EDIT_METHODS and seems to be on by default in m143 and m144. For now I am trying to remove the define and see what else needs fixing, but it will affect a lot of existing code as it basically removes about 31 SkPath methods we use... that will break almost everybody's code which uses SkPath.

Sigh. Cc. @kyamagu

[kyamagu]

Hmm, that's going to be a significant breaking change...