This patch adds the newly added support for contexts in V8 Tracing, as well
as use it to mark all the entry points for a V8 Isolate.

Update for reland: The current tracing interface needs to be updated (AddTraceEvent),
but the embedders need to migrate to the new version before removing the old version.
(Reland of: https://codereview.chromium.org/1686233002)

The revert happened because the 2 signatures of the old and new AddTraceEvent where different
so it threw an overload-virtual error on cross arm debug. This issue is temporary, and to solve
it, I added an implementation of the old and new everywhere until the embedder implements the new.

BUG=v8:4565
LOG=N

R=jochen@chromium.org

Review URL: https://codereview.chromium.org/1704253002

Cr-Commit-Position: refs/heads/master@{#34332}

Revert of Add Scoped Context Info (Isolate) to V8 Traces (patchset #5 id:80001 of https://codereview.chromium.org/1686233002/ )

Reason for revert:
[Sheriff] Breaks arm cross-compile:
https://build.chromium.org/p/client.v8/builders/V8%20Arm%20-%20debug%20builder/builds/7825/

Original issue's description:
> Add Scoped Context Info (Isolate) to V8 Traces
>
> This patch adds the newly added support for contexts in V8 Tracing, as well
> as use it to mark all the entry points for a V8 Isolate.
>
> BUG=v8:4565
> LOG=N
>
> Committed: https://crrev.com/44823c3c6965966c63b7e2e2361d0f2a58d196ea
> Cr-Commit-Position: refs/heads/master@{#34092}

TBR=jochen@chromium.org,fmeawad@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4565

Review URL: https://codereview.chromium.org/1710573002

Cr-Commit-Position: refs/heads/master@{#34095}

This patch adds the newly added support for contexts in V8 Tracing, as well
as use it to mark all the entry points for a V8 Isolate.

BUG=v8:4565
LOG=N

Review URL: https://codereview.chromium.org/1686233002

Cr-Commit-Position: refs/heads/master@{#34092}

BUG=559117
LOG=N

Review URL: https://codereview.chromium.org/1684963002

Cr-Commit-Position: refs/heads/master@{#34042}

This is based on the Skia Implementation.

More on the project can be found here:
https://docs.google.com/a/chromium.org/document/d/1_4LAnInOB8tM_DLjptWiszRwa4qwiSsDzMkO4tU-Qes/edit#heading=h.p97rw6yt8o2j

The V8 Tracing platform will replace the isolate->event_logger().
But since the current embedders (namely chromium) currently use the isolate->event_logger, I made the default implementation (event-tracer) call into isolate->event_logger if an event_logger was set.
Once the embedders properly implement the interface (for example in chromium it would look like this: https://codereview.chromium.org/707273005/), the default implementation will be doing nothing.

Once the embedders side is fixed, we will change how V8 uses the tracing framework beyond the call from Logger:CallEventLogger. (which would also include a d8 implementation)

BUG=v8:4560
LOG=N

Review URL: https://codereview.chromium.org/988893003

Cr-Commit-Position: refs/heads/master@{#32959}