V8 has had a trace event macro interface for while, but without a tracing
controller a standalone V8 would be unable to collect traces.

This CL introduces a complete Tracing Controller system for V8.
It is fully function except that it does not yet store trace event args.

This CL has a few components,
The tracing controller itself, contributed by the author of this CL
The Trace config (including the parser), contributed by lpy@
The Trace Object, Trace Writer, and Trace Buffer are all contributed by rksang@

BUG=v8:4561
LOG=N

The original CL was failing the V8 Arm Builder:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Arm%20-%20builder/builds/2456
and the V8 Mips Builder:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Mips%20-%20builder/builds/2506

The failure is due to undefined behavior of CHECK_EQ of 2 const char*

Fix in patch #1

Committed: https://crrev.com/3d598452679ce208ad9b2f48e0fb3fae352ce375
Cr-Commit-Position: refs/heads/master@{#38073}

patch from issue 2137013006 at patchset 200001 (http://crrev.com/2137013006#ps200001)

Review-Url: https://codereview.chromium.org/2183923004
Cr-Commit-Position: refs/heads/master@{#38104}