Make Function, Supplier, and Predicate extend the corresponding j.u.f interfaces
Make Equivalence implement j.u.f.BiPredicate
Make CharMatcher implement IntPredicate so it can be used on CharSequence.stream()
Rewrite c.g.c.base.Functions to accept j.u.f interfaces but return c.g.c interfaces
Rewrite c.g.c.base.Predicates to accept j.u.f interfaces but return c.g.c interfaces
Rewrite composition methods on c.g.c.base.{Predicate, Function}, e.g. Predicate.andThen.
Fix an issue where c.g.c.base.Predicate.{and,or} conflicted with CharMatcher's {and,or} signature
Fix some inadvertent bugs with proper types in c.g.c.base.Functions
Provide a collector() method on Joiner.
Add a splitToStream method on Splitter.
Replace Iterators.emptyModifiableIterator with Collections.emptyIterator
Rewrite c.g.c.c.Iterators to accept j.u.f functional types
Optimize Iterators methods' forEachRemaining implementations
Rewrite c.g.c.c.Iterables to accept j.u.f functional types
Reimplement Iterable-returning methods in Iterables with lambdas where possible
Rewrite c.g.c.c.Collections2 to accept j.u.f functional types
Optimize Collections2 with new Stream utilities
Rewrite c.g.c.c.Lists to accept j.u.f functional types, and provide decent stream() implementations to the Lists it returns
Rewrite c.g.c.c.{Sets,Platform,Maps} to accept j.u.f functional types
Optimize the stream implementations in c.g.c.c.Sets