move SkDevice.h and SkBitmapDevice.h contents in to src headers

BUG=skia:

Change-Id: I3d8d313f0500c13db21cb973fed4064ec3816912
Reviewed-on: https://skia-review.googlesource.com/7082
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>
19 files changed