[index/AST] Add references for ObjC getter=/setter= property attributes and related property getter/setter role fixes

This enhances the AST to keep track of locations of the names in those ObjC property attributes, and reports them for indexing.

Patch by Nathan Hawes!
https://reviews.llvm.org/D30907

llvm-svn: 297972
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index 2a7768a..ed405b5 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -4580,8 +4580,10 @@
   ToProperty->setPropertyAttributes(D->getPropertyAttributes());
   ToProperty->setPropertyAttributesAsWritten(
                                       D->getPropertyAttributesAsWritten());
-  ToProperty->setGetterName(Importer.Import(D->getGetterName()));
-  ToProperty->setSetterName(Importer.Import(D->getSetterName()));
+  ToProperty->setGetterName(Importer.Import(D->getGetterName()),
+                            Importer.Import(D->getGetterNameLoc()));
+  ToProperty->setSetterName(Importer.Import(D->getSetterName()),
+                            Importer.Import(D->getSetterNameLoc()));
   ToProperty->setGetterMethodDecl(
      cast_or_null<ObjCMethodDecl>(Importer.Import(D->getGetterMethodDecl())));
   ToProperty->setSetterMethodDecl(