This revision of libaom has some conflicts with our vendor script
and build system. A number of new .asm files have the same basename
as .c files, which our build system cannot handle.
To work around this, I manually renamed the conflicting
files in the filesystem and sources.mozbuild.
Also add av1_convolve_scale_sse4.c to sources.mozbuild manually.
This is needed by the build but for some reason isn't picked up
by generate_sources_mozbuild.sh.
Visual Studio 2015u3 fails to compile reconintra.c for win32
debug targets. It's confused by the #if conditional inside
the assert macro expansion.
The checks are obsolete upstream. Address the issue by
duplicating the assert calls for each branch of the
conditional.
