... or sometimes by FATAL(...) to give a better error message.
The benefit of UNREACHABLE() over CHECK(false) is that the compiler
knows that this macro will never return, hence we can omit the return
of a dummy value afterwards.

R=neis@chromium.org

Change-Id: I14e6a4f1d75f1338f481bd1520d841fd383d6202
Reviewed-on: https://chromium-review.googlesource.com/832431Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50214}

v8 allows the embedder to specify a global template to use when
creating a new context. However, v8 does not use the supplied
template directly when creating the global proxy: it creates a
unique template for each global proxy. However, this is problematic
for remote contexts: functions cannot use strict receiver checks
with the remote context, as the global template will never match
the global proxy.

To fix this, remote contexts now also include a remote global
object in the prototype chain that is instantiated with the global
template. This mirrors the way the global proxy is configured for a
full v8 context, and allows strict receiver checks to work.

BUG=527190

Review-Url: https://codereview.chromium.org/2677653002
Cr-Commit-Position: refs/heads/master@{#43361}

When v8 fails an access check, it invokes a helper to try to see if it
can service the request via an access check interceptor. Invoking the
access check interceptor can throw an exception (e.g. a SecurityError).

Unfortunately, the failed access check property helpers and the
interceptor helpers don't agree on how to propagate the exception: if
the interceptor helper detects a scheduled exception, it promotes the
exception to a pending exception and returns to the failed access check
property helper.

The failed access check property helper also has an early return in
case of a scheduled exception. However, this doesn't work, as the
previously thrown exception is no longer scheduled, as it's been
promoted to a pending exception. Thus, the failed access check property
helper always end up calling the failed access check callback as well.
Since Blink's implementation of the failed access check callback also
throws an exception, this conflicts with the previously-thrown,
already-pending exception.

With this patch, the failed access check property helpers check for a
pending exception rather than a scheduled exception after invoking the
interceptor, so the exception can be propagated correctly.

BUG=v8:5715
R=yangguo@chromium.org,jochen@chromium.org

Review-Url: https://codereview.chromium.org/2550423002
Cr-Commit-Position: refs/heads/master@{#41556}

BUG=chromium:618305
R=verwaest@chromium.org
CC=dcheng@chromium.org,haraken@chromium.org

Review-Url: https://codereview.chromium.org/2162443002
Cr-Commit-Position: refs/heads/master@{#37867}

Such an object can be used to later create a context from it. It has to
have access checks with handlers enabled, as it cannot be accessed
otherwise.

BUG=chromium:618305
R=verwaest@chromium.org

Review-Url: https://codereview.chromium.org/2107673003
Cr-Commit-Position: refs/heads/master@{#37594}

This superseeds all-can-read/all-can-write properties

BUG=chromium:618305
R=verwaest@chromium.org

Review-Url: https://codereview.chromium.org/2087823002
Cr-Commit-Position: refs/heads/master@{#37286}