Now that {WasmCode} objects are no longer specific to an instance, it is
no longer needed to patch code when the last instance is finalized. The
code specialization in {WasmCompiledModule::Reset} is no longer needed.

R=clemensh@chromium.org

Change-Id: I430e7f7258d309916de1188d47677c7feb8123b0
Reviewed-on: https://chromium-review.googlesource.com/1057488Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53155}