This CL removes some unused variables, and changes some integers to
unsigned integers. On some platforms, we were getting compiler errors
and unit test failures.
Merge from Widevine repo of http://go/wvgerrit/23840
Use unsigned integer literals
Merge from Widevine repo of http://go/wvgerrit/23767
Fix Gyp Files
Merge from Widevine repo of http://go/wvgerrit/23500
Remove unused variables
bug: 31458046
Change-Id: I4dfec95ae49187262552fbbf322f3310ab777826