Use 'override/final' instead of 'virtual' for overridden methods

Summary:
The patch is generated using clang-tidy misc-use-override check.

This command was used:

  tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
    -checks='-*,misc-use-override' -header-filter='llvm|clang' -j=32 -fix

Reviewers: dblaikie

Reviewed By: dblaikie

Subscribers: klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D8926

llvm-svn: 234678
diff --git a/clang/lib/Frontend/Rewrite/RewriteObjC.cpp b/clang/lib/Frontend/Rewrite/RewriteObjC.cpp
index 5802ba7..170c209 100644
--- a/clang/lib/Frontend/Rewrite/RewriteObjC.cpp
+++ b/clang/lib/Frontend/Rewrite/RewriteObjC.cpp
@@ -193,7 +193,7 @@
                 DiagnosticsEngine &D, const LangOptions &LOpts,
                 bool silenceMacroWarn);
 
-    ~RewriteObjC() {}
+    ~RewriteObjC() override {}
 
     void HandleTranslationUnit(ASTContext &C) override;
 
@@ -511,8 +511,8 @@
                 bool silenceMacroWarn) : RewriteObjC(inFile, OS,
                                                      D, LOpts,
                                                      silenceMacroWarn) {}
-    
-    ~RewriteObjCFragileABI() {}
+
+    ~RewriteObjCFragileABI() override {}
     void Initialize(ASTContext &context) override;
 
     // Rewriting metadata