- SSE2 files are unfortunately now mixed-case, _SSE2 or _sse2.
- Adds lists for SSSE3 and SSE4 files.
- Remove SkDocument_PDF_None.cpp
- Remove a few more references to animator.
- Exclude private headers from HDRS.
- Formatting and notes.
BUG=skia:
Review URL: https://codereview.chromium.org/1298003007