Move writePatch() to private now that PatchWriter isn't subclassed

The HW stroke tessellator had subclassed PatchWriter and called
writePatch() directly. Now the fixed-count variants all just use
the trait templates to configure PatchWriter directly.

Bug: skia:13263, skia:13056
Change-Id: I51c674968fe46974b217069909d71446a0d829c9
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/534568
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
1 file changed