Implement some framework for defaulted constructors.

There's some unused stuff for now.

llvm-svn: 130912
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index dc881ba..8e95cfe 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -2397,7 +2397,8 @@
                                             NameInfo, T, TInfo, 
                                             FromConstructor->isExplicit(),
                                             D->isInlineSpecified(), 
-                                            D->isImplicit());
+                                            D->isImplicit(),
+                                      FromConstructor->isExplicitlyDefaulted());
   } else if (isa<CXXDestructorDecl>(D)) {
     ToFunction = CXXDestructorDecl::Create(Importer.getToContext(),
                                            cast<CXXRecordDecl>(DC),