This introduces PooledLambda - a way of obtaining lambdas without the
allocations overhead.
See PooledLambda javadoc for a guide and PooledLambdaSample for code samples
of useful usages.
Test: ensure samples of PooledLambdaSample work as described.
Change-Id: I46f8ad27bc1de07e19f6e39f89d2cafe4238497a