remove use of tuple in favor of struct. Change-Id: If3b1aa5c2fc3cfe1446fff7a8fd270f2ca85fedf
This is to replace vp10/common/reconinter.c:build_masked_compound. Functionality is equivalent, but the interface is slightly more generic. Total encoder speedup with ext-inter: ~7.5% Change-Id: Iee18b83ae324ffc9c7f7dc16d4b2b06adb4d4305