Add use counters for ReadableStream methods

Add use counters for getReader, pipeThrough and pipeTo.

Bug: 828034
Change-Id: I268373d8ac518919bd74f400e8ec3aea91a11690
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1554205
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Commit-Queue: Adam Rice <ricea@chromium.org>
Auto-Submit: Yutaka Hirano <yhirano@chromium.org>
Reviewed-by: Adam Rice <ricea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#648070}
3 files changed