Merge from widevine repo of http://go/wvgerrit/14668
This CL modifies the multiplication routine to avoid memory cache
misses. This shows a 10-20% speed improvment in license requests on
an x86.
Level 3 library version:
level3/arm/libwvlevel3.a Level3 Library Jun 15 2015 14:09:24
level3/x86/libwvlevel3.a Level3 Library Jun 15 2015 14:09:10
bug: 18252910
Change-Id: I4429324374de46d1d710d5fcac80f7ed363c696c