With this CL d8 exits with an error code if there is an unhandled
promise rejection, e.g. due tue a failed assertion in a promise. Up
until now these assertions were just ignored.

Bug: v8:10556
Change-Id: I25f20e4be45a2de130562deb15f6a144f0ac976f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2238569Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68503}

This replaces Runtime_RunMicrotasks with Runtime_PerformMicrotaskCheckpoint.

RunMicrotasks forcibly runs Microtasks even when the microtasks are suppressed,
and may causes nested Microtasks in a problematic way. E.g. that confuses
v8::MicrotasksScope::IsRunningMicrotasks() and GetEnteredOrMicrotaskContext().

OTOH, PerformMicrotaskCheckpoint() doesn't run cause the failure as it
respects the microtask suppressions.

As all existing tests don't call RunMicrotasks() in the suppressed situation
(like Promise.resolve().then(()=>{%RunMicrotasks();})), this change should
not affect to these tests.

Change-Id: Ib043a0cc8e482e022d375084d65ea98a6f54ef3d
Reviewed-on: https://chromium-review.googlesource.com/c/1360095Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Taiju Tsuiki <tzik@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58068}

This moves AsyncFunctionAwait{Caught,Uncaught} to CSA, and removes
async-await.js.

BUG=v8:5639

Review-Url: https://codereview.chromium.org/2643023002
Cr-Commit-Position: refs/heads/master@{#42579}

It shipped with Chrome 55 stable.

R=littledan@chromium.org

Review-Url: https://codereview.chromium.org/2621173002
Cr-Commit-Position: refs/heads/master@{#42203}

-- Moves promiseHasHandlerSymbol to inobject property
-- Ports PromiseResolveClosure to TF
-- Fix a non spec async-await test which fails now because we do a map
check for native promise check (instead of IsPromise). Changing the
constructor (in the test) invalidates the map check.

This patch results in a 7.1% performance improvement in the bluebird
benchmark (over 5 runs).

BUG=v8:5343

Review-Url: https://codereview.chromium.org/2541283002
Cr-Commit-Position: refs/heads/master@{#41569}

- Don't read .constructor when returning a Promise from an async function.
  Instead, call out to the internals of Promise.resolve directly.
  This is done by adding back in an "optimization" from an earlier form of
  the async/await code written by Caitlin Potter.
- Async functions always return a new Promise with a distinct identity,
  even if they simply return another Promise.

R=caitp@igalia.com
BUG=v8:4483

Review-Url: https://codereview.chromium.org/2219623002
Cr-Commit-Position: refs/heads/master@{#38404}