Support ObjC implementation decls for PCH.

Strictly speaking, implementations don't go in headers but there's no law against it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@110567 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/PCHWriterDecl.cpp b/lib/Frontend/PCHWriterDecl.cpp
index ec5c575..6a78140 100644
--- a/lib/Frontend/PCHWriterDecl.cpp
+++ b/lib/Frontend/PCHWriterDecl.cpp
@@ -468,7 +468,8 @@
 void PCHDeclWriter::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
   VisitObjCImplDecl(D);
   Writer.AddDeclRef(D->getSuperClass(), Record);
-  // FIXME add writing of IvarInitializers and NumIvarInitializers.
+  Writer.AddCXXBaseOrMemberInitializers(D->IvarInitializers,
+                                        D->NumIvarInitializers, Record);
   Code = pch::DECL_OBJC_IMPLEMENTATION;
 }
 
@@ -1096,8 +1097,8 @@
 /// relatively painless since they would presumably only do it for top-level
 /// decls.
 static bool isRequiredDecl(const Decl *D, ASTContext &Context) {
-  // File scoped assembly must be seen.
-  if (isa<FileScopeAsmDecl>(D))
+  // File scoped assembly or obj-c implementation must be seen.
+  if (isa<FileScopeAsmDecl>(D) || isa<ObjCImplementationDecl>(D))
     return true;
 
   return Context.DeclMustBeEmitted(D);