Sometimes a function would have multiple signatures in the IDL files
with the difference just being some of the arguments are optional.
This patch improves the deduplication logic to correctly support
array.splice(start, ?deleteCount, ...items)
Change-Id: Ie9230d54dadd1c8c7cadbb92afc37fbfa87ea857
Reviewed-on: https://chromium-review.googlesource.com/1062885
Reviewed-by: Andrey Lushnikov <lushnikov@chromium.org>
Commit-Queue: Joel Einbinder <einbinder@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#559342}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: ddcb027a039f212e0701f7118ea7dd8b8cea65b4