... containing Tuple2 value instead of two properties. This CL reduces the
number of property queries in FunctionToString to one and it is memory-neutral.

Change-Id: Ia6fa267f3e5b6670013f1da3e03cd70bf24dd65a
Reviewed-on: https://chromium-review.googlesource.com/730744Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48926}