Unique_ptrify PPCallbacks ownership.

Unique_ptr creation stil needs to be moved earlier at some of the call sites.

llvm-svn: 217474
diff --git a/clang/lib/Frontend/DependencyFile.cpp b/clang/lib/Frontend/DependencyFile.cpp
index ce33086..22ed38f 100644
--- a/clang/lib/Frontend/DependencyFile.cpp
+++ b/clang/lib/Frontend/DependencyFile.cpp
@@ -121,7 +121,8 @@
 
 DependencyCollector::~DependencyCollector() { }
 void DependencyCollector::attachToPreprocessor(Preprocessor &PP) {
-  PP.addPPCallbacks(new DepCollectorPPCallbacks(*this, PP.getSourceManager()));
+  PP.addPPCallbacks(
+      llvm::make_unique<DepCollectorPPCallbacks>(*this, PP.getSourceManager()));
 }
 void DependencyCollector::attachToASTReader(ASTReader &R) {
   R.addListener(llvm::make_unique<DepCollectorASTListener>(*this));
@@ -203,7 +204,7 @@
     PP.SetSuppressIncludeNotFoundError(true);
 
   DFGImpl *Callback = new DFGImpl(&PP, Opts);
-  PP.addPPCallbacks(Callback); // PP owns the Callback
+  PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(Callback));
   return new DependencyFileGenerator(Callback);
 }