Make SkMemory.h and adjust all files for usage.

Make SkMemory.h and adjust all files for usage.

This will be rolled out in three stages:
1) make SkMemory.h and have SkTypes.h include it.
2) Adjust chromium and android.
3) no long include SkMemory.h in SkTypes.h

Change-Id: If360ef5e1164d88f50b03f279e2e963ca2f57d5d
Reviewed-on: https://skia-review.googlesource.com/9874
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Herb Derby <herb@google.com>