Fix closure var_export

Summary: Just export the name of the class to avoid infinite recursion.

Fixes #4176

Reviewed By: @fredemmott

Differential Revision: D1668260

Signature: t1:1668260:1415405711:bc1f17b7b39fc980cdff4ae8a4637fcdee085784
If there is no socket error, return an empty string

Summary: Right now we return `NULL`. PHP 5.x returns an empty string. Let's be compatible.

Fixes #3066

Reviewed By: @markw65

Differential Revision: D1668138

Signature: t1:1668138:1415410047:7339d837f79e4bda755cf5cbc2d8c716b5635c19
ftell() for sockets shouldn't be supported. So always return 0.

Summary: Right now, for sockets, we return the number of bytes written to the socket when we call
`ftell()`. But this shouldn't be the case.

See ESPIPE ... http://pubs.opengroup.org/onlinepubs/009695399/functions/ftell.html

PHP 5.x returns 0 when calling `ftell()` on a socket, so that's what I propose we doo.

This is a one line change, which can be the scariest. :)

Let me know if I am off base, but this does fix an HHVM OSS issue.

Fixes #3018

Reviewed By: @sgolemon

Differential Revision: D1668651

Signature: t1:1668651:1415413974:5c040e68e2b4ca1f7a206eef6eca35f54eac12b0
Test runner should print correct options to re-run failing tests

Summary: We were just printing `test/run <testname` even if options were provided. This fixes that.

Fixes #3916

Reviewed By: @paulbiss

Differential Revision: D1665442

Signature: t1:1665442:1415498351:98ea82d6286410ea07a28e4c7641bce59848fdd2
Updated the package version in CMakeLists.txt

Summary: This should be `3.4.0` in the 3.4 branch.
Closes https://github.com/facebook/hhvm/pull/4181

Reviewed By: @JoelMarcey

Differential Revision: D1669153

Signature: t1:1669153:1415514126:b9abcf702f328ac51c6ead9966b5d43238d788fe
Move MInstrState from C++ stack to RDS header

Summary: Move MInstrState to be with the other VM registers in the RDS header,
rather than reserving space for it on the native stack in enterTCHelper. This
is one step on the way to allowing arbitrary rsp manipulations during
tracelets. I also removed MInstrState's tvVal and tvResult members since
they've been unused for a while.

Reviewed By: @jasone

Differential Revision: D1665434
Convert ext/spl to HNI

Fixes #3947
This was a missing clone in the assignment.
null_variant => null; only clone on objects
Move some implementations back to php

And add test for #3947
HNI doesn't know null_string, so check for empty instead
Add VMRegAnchor to iterator_apply
Add VMRegAnchor
Fix return type annotation on iterator_to_array