Apply modernize-use-default to clang.

Summary: Replace empty bodies of default constructors and destructors with '= default'.

Reviewers: bkramer, klimek

Subscribers: klimek, alexfh, cfe-commits

Differential Revision: http://reviews.llvm.org/D13890

llvm-svn: 250822
diff --git a/clang/lib/Frontend/Rewrite/RewriteObjC.cpp b/clang/lib/Frontend/Rewrite/RewriteObjC.cpp
index 204820b..9d9be2c 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() override {}
+    ~RewriteObjC() override = default;
 
     void HandleTranslationUnit(ASTContext &C) override;
 
@@ -512,7 +512,7 @@
                                                      D, LOpts,
                                                      silenceMacroWarn) {}
 
-    ~RewriteObjCFragileABI() override {}
+    ~RewriteObjCFragileABI() override = default;
     void Initialize(ASTContext &context) override;
 
     // Rewriting metadata