Push DeclGroup much farther throughout the compiler.  Now the various
productions (except the already broken ObjC cases like @class X,Y;) in 
the parser that can produce more than one Decl return a DeclGroup instead
of a Decl, etc.

This allows elimination of the Decl::NextDeclarator field, and exposes
various clients that should look at all decls in a group, but which were
only looking at one (such as the dumper, printer, etc).  These have been
fixed.

Still TODO:

1) there are some FIXME's in the code about potentially using
DeclGroup for better location info.
2) ParseObjCAtDirectives should return a DeclGroup due to @class etc.
3) I'm not sure what is going on with StmtIterator.cpp, or if it can
   be radically simplified now.
4) I put a truly horrible hack in ParseTemplate.cpp.

I plan to bring up #3/4 on the mailing list, but don't plan to tackle
#1/2 in the short term.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@68002 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/StmtIterator.cpp b/lib/AST/StmtIterator.cpp
index 94829c0..20024f5 100644
--- a/lib/AST/StmtIterator.cpp
+++ b/lib/AST/StmtIterator.cpp
@@ -67,12 +67,11 @@
   if (inDecl()) {
     assert (decl);
     
+    // FIXME: SIMPLIFY AWAY.
     if (ImmediateAdvance)
-      decl = decl->getNextDeclarator();
-    
-    for ( ; decl ; decl = decl->getNextDeclarator())
-      if (HandleDecl(decl))
-        return;
+      decl = 0;
+    else if (HandleDecl(decl))
+      return;
   }
   else {
     assert (inDeclGroup());