Rename SkOrientationMarker.cpp

Bug: skia:8046

The only method it has in it is SkParseEncodedOrigin, so rename to
match. As with the original file, this is here so we can update
Chromium's build file, then land the CL which makes it do something.

Change-Id: Idc8bf44ea3d3f251bd122858e10313c31d0eeec6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/243426
Commit-Queue: Leon Scroggins <[email protected]>
Commit-Queue: Mike Klein <[email protected]>
Auto-Submit: Leon Scroggins <[email protected]>
Reviewed-by: Mike Klein <[email protected]>

Author: LeonScroggins