[PATCH] Remove pimpl class from PassRegistry.

[Zachary Turner]

================
Comment at: include/llvm/PassInfo.h:1
@@ +1,2 @@
+//===- llvm/PassInfo.h - Pass Info class ------------------------*- C++ -*-===//
+//
----------------
David Blaikie wrote:
> I take it you had to split this out to resolve a dependency that wasn't exposed when everything was pmpld away?
Yes, I actually updated the description on Phab, but it didn't send out an email notification for that.  Basically, the pimpl has a unique_ptr<PassInfo>, and PassSupport.h already includes PassRegistry.h, so I couldn't have PassRegistry.h include PassSupport.h to get this class.

Plus, one class-one file is just better when the classes are non-trivial :)

http://reviews.llvm.org/D4107