Revert[3] "move some public headers into private"

This reverts commit 9d20ee57d72a3850a6b51f2f2b00e00978be3864.

BUG=skia:
TBR=

failures here: https://codereview.chromium.org/1286103004

Review URL: https://codereview.chromium.org/1290733002
11 files changed