Reintroduce the ASTConsumer/ASTUnit fix from r110610, it has nothing to do with the breakage.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@110840 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index fe4768d..bbe2ec5 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -320,6 +320,9 @@
       Unit.addTopLevelDecl(D);
     }
   }
+
+  // We're not interested in "interesting" decls.
+  void HandleInterestingDecl(DeclGroupRef) {}
 };
 
 class TopLevelDeclTrackerAction : public ASTFrontendAction {
diff --git a/lib/Frontend/PCHReader.cpp b/lib/Frontend/PCHReader.cpp
index 1bfc138..68acbb2 100644
--- a/lib/Frontend/PCHReader.cpp
+++ b/lib/Frontend/PCHReader.cpp
@@ -2262,7 +2262,7 @@
   SavedStreamPosition SavedPosition(DeclsCursor);
 
   ReadingKindTracker ReadingKind(Read_Type, *this);
-  
+
   // Note that we are loading a type record.
   Deserializing AType(this);
 
@@ -3027,7 +3027,7 @@
   while (!InterestingDecls.empty()) {
     DeclGroupRef DG(InterestingDecls.front());
     InterestingDecls.pop_front();
-    Consumer->HandleTopLevelDecl(DG);
+    Consumer->HandleInterestingDecl(DG);
   }
 }