Improve location fidelity of objc decls.

-Add the location of the class name to all objc container decls, not just ObjCInterfaceDecl.
-Make objc decls consistent with the rest of the NamedDecls and have getLocation() point to the
 class name, not the location of '@'.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141061 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Serialization/ASTWriterDecl.cpp b/lib/Serialization/ASTWriterDecl.cpp
index 62459f7..81394c2 100644
--- a/lib/Serialization/ASTWriterDecl.cpp
+++ b/lib/Serialization/ASTWriterDecl.cpp
@@ -427,6 +427,7 @@
 
 void ASTDeclWriter::VisitObjCContainerDecl(ObjCContainerDecl *D) {
   VisitNamedDecl(D);
+  Writer.AddSourceLocation(D->getAtStartLoc(), Record);
   Writer.AddSourceRange(D->getAtEndRange(), Record);
   // Abstract class (no need to define a stable serialization::DECL code).
 }
@@ -463,7 +464,6 @@
   Writer.AddDeclRef(D->getCategoryList(), Record);
   Record.push_back(D->isForwardDecl());
   Record.push_back(D->isImplicitInterfaceDecl());
-  Writer.AddSourceLocation(D->getClassLoc(), Record);
   Writer.AddSourceLocation(D->getSuperClassLoc(), Record);
   Writer.AddSourceLocation(D->getLocEnd(), Record);
   Code = serialization::DECL_OBJC_INTERFACE;
@@ -542,7 +542,6 @@
     Writer.AddSourceLocation(*PL, Record);
   Writer.AddDeclRef(D->getNextClassCategory(), Record);
   Record.push_back(D->hasSynthBitfield());
-  Writer.AddSourceLocation(D->getAtLoc(), Record);
   Writer.AddSourceLocation(D->getCategoryNameLoc(), Record);
   Code = serialization::DECL_OBJC_CATEGORY;
 }