Rename Diagnostic to DiagnosticsEngine as per issue 5397


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@140478 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/unittests/AST/APValueTest.cpp b/unittests/AST/APValueTest.cpp
index ae054b3..0183938 100644
--- a/unittests/AST/APValueTest.cpp
+++ b/unittests/AST/APValueTest.cpp
@@ -24,7 +24,7 @@
   class LastDiagnosticString : public DiagnosticClient {
     SmallString<64> LastDiagnostic;
   public:
-    virtual void HandleDiagnostic(Diagnostic::Level DiagLevel,
+    virtual void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
                                   const DiagnosticInfo &Info) {
       LastDiagnostic.clear();
       Info.FormatDiagnostic(LastDiagnostic);
@@ -36,7 +36,7 @@
   const IntrusiveRefCntPtr<DiagnosticIDs> DiagIDs;
   const unsigned diag_just_format;
   LastDiagnosticString LastDiagnostic;
-  Diagnostic Diag;
+  DiagnosticsEngine Diag;
 
 public:
   DiagnosticOutputGetter()