deps: backport c281c15 from V8's upstream
deps: backport c281c15 from V8's upstream

Backport c281c15d6dab8370a7805f0717502d260e0ad433 from V8's upstream to
allow post-mortem debugging tools to inspect Buffer instances' length.

Original commit message:

  Add JSTypedArray's length in post-mortem metadata.

  BUG=
  R=bmeurer@chromium.org

  Review URL: https://codereview.chromium.org/1363683002

  Cr-Commit-Position: refs/heads/master@{#30873}

PR: #3031
PR-URL: https://github.com/nodejs/node/pull/3031
Reviewed-By: Trevor Norris <9cb5491eb5770dd8e0bf77a8a0335abf5f0488c5@gmail.com>

dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node