this avoids duplicates between these trees and dsp/, e.g., enc/tree.c,
dec/tree.c, making pulling the whole library source tree into one target
possible
BUG=webp:279
Change-Id: I060a614833c7c24ddd37bf641702ae6a5eef1775
generates a stub function when the specific architecture is not enabled,
exposing a symbol in the module, avoiding a compiler warning
Change-Id: Ia9336e57466a9b5241b85c1c95838e91c9283147
The MIPS code for cost is not updated yet, that's why i keep Residual::*cost
around for now. Should be removed in favor of *costs later.
Change-Id: Id1d09a8c37ea8c5b34ad5eb8811d6a3ec6c4d89f