The previous hack with HInstanceOfKnownGlobal was not only slower,
but also very brittle and required a lot of weird hacks to support it. And
what's even more important it wasn't even correct (because a map check
on the lhs is never enough for instanceof).
The new implementation provides a sane runtime implementation
for InstanceOf plus a fast case in the InstanceOfStub, combined with
a proper specialization in the case of a known global in CrankShaft,
which does only the prototype chain walk (coupled with a code
dependency on the known global).
As a drive-by-fix: Also fix the incorrect Object.prototype.isPrototypeOf
implementation.
BUG=v8:4376
LOG=y
Review URL: https://codereview.chromium.org/1304633002
Cr-Commit-Position: refs/heads/master@{#30342}
