start switching decls over to using an allocator controlled by ASTContext.  
Right now only some ctors are switched over.  I need to switch them all
over so I can change the dtor over.

This lets us experiment with region allocation and other things in the 
future.

llvm-svn: 48390
7 files changed
tree: e023956e1791f067cbae60c666bb75571cde1bc8
  1. clang/
  2. llvm/