This patch was to fix issue 924:
https://code.google.com/p/webm/issues/detail?id=924
The SECTION_RODATA macro was modified to support macho32 format.
The sub-pixel functions were modified to pass in 2 more parameters
to handle the global offsets for PIC build.
Change-Id: I3bfcd336bcae945edf300bca4ab40376a2628cd4