remove trigger_error from sncompress

Summary: These are hilariously causing a 20% perf regression. I'll put them back once I can migrate us.

Reviewed By: @JoelMarcey

Differential Revision: D1462853
Fix codegen bug when Class* doesn't fit in a dword

Summary: We were assuming that Class* fits in 32-bits, but that's not
necessarily the case.  If it doesn't fit, fall back to using a scratch
register.

Reviewed By: @markw65

Differential Revision: D1465175
make DynamicExtensions work in ini

Summary: I need to change all the callsites, but this one has been asked for the most.

Reviewed By: @fredemmott

Differential Revision: D1464698
Hotfix for #3289 `ReflectionParameter#getClass()` on `callable` type hint should not raise exceptions

Summary: See #3289 - `ReflectionParameter#getClass()` on `callable` type hint should not raise exceptions

PR is NOT tested as I didn't have time to build HHVM today, so I'll have to trust travis here.

Closes https://github.com/facebook/hhvm/pull/3290

Reviewed By: @ptarjan

Differential Revision: D1460709

Pulled By: svcscm
run usercode before ending the request

Summary: Currently, the following happens at the end of a request:
onSendEnd -> run postsend functions -> hphp_context_exit

However, hphp_context_exit can call destructors for objects that are
alive at the end of request. This usercode should be allowed to send
output. This causes a circular reference issue because postsend
functions might need to access those objects.

When we don't have a postsend function, preserve Zend compatibility by
delaying the execution of onSendEnd.

Closes https://github.com/facebook/hhvm/pull/3279

Reviewed By: @markw65

Differential Revision: D1465876

Pulled By: svcscm
Move flaky tests to test/zend/bad

Summary: More of what happened in D1465647

Reviewed By: mcl, bertrand

Differential Revision: D1466742
Fix insertion order in eliminateJmp

Summary: Incrementing the iterator was causing the insertions to happen in kind
of random places.  It seems like the correct thing to do is not to increment.
This probably isn't exercised outside of wholecfg.

Reviewed By: @edwinsmith

Differential Revision: D1463010