This CL is a manual revert of 3e78711c.

Adding the fast path did not result in any performance improvement,
and actually decreased DataView performance in the performance test.

Change-Id: I149670088b07c31e44d93ed65505254ec0caf8ba
Reviewed-on: https://chromium-review.googlesource.com/1126925Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Commit-Queue: Théotime Grohens <theotime@google.com>
Cr-Commit-Position: refs/heads/master@{#54251}