Keep track when a ObjC interface/protocol was initially created as a forward reference.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@142230 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ASTImporter.cpp b/lib/AST/ASTImporter.cpp
index ae2b890..7e252d1 100644
--- a/lib/AST/ASTImporter.cpp
+++ b/lib/AST/ASTImporter.cpp
@@ -3110,7 +3110,8 @@
     if (!ToProto) {
       ToProto = ObjCProtocolDecl::Create(Importer.getToContext(), DC,
                                          Name.getAsIdentifierInfo(), Loc,
-                                         Importer.Import(D->getAtStartLoc()));
+                                         Importer.Import(D->getAtStartLoc()),
+                                         D->isInitiallyForwardDecl());
       ToProto->setForwardDecl(D->isForwardDecl());
       ToProto->setLexicalDeclContext(LexicalDC);
       LexicalDC->addDecl(ToProto);