The new names for memory.drop and table.drop are data.drop and elem.drop
respectively. See
https://github.com/WebAssembly/bulk-memory-operations/issues/23 and
https://github.com/WebAssembly/bulk-memory-operations/pull/46.

Change-Id: I07aab8448fabe24eb9734dc7dac6f91c570cb553
Reviewed-on: https://chromium-review.googlesource.com/c/1446148
Commit-Queue: Ben Smith <binji@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59261}