[llvm] Migrate llvm::make_unique to std::make_unique

Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
diff --git a/llvm/lib/DebugInfo/PDB/Native/DbiModuleDescriptorBuilder.cpp b/llvm/lib/DebugInfo/PDB/Native/DbiModuleDescriptorBuilder.cpp
index 20b6c61..4197347 100644
--- a/llvm/lib/DebugInfo/PDB/Native/DbiModuleDescriptorBuilder.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/DbiModuleDescriptorBuilder.cpp
@@ -180,12 +180,12 @@
 void DbiModuleDescriptorBuilder::addDebugSubsection(
     std::shared_ptr<DebugSubsection> Subsection) {
   assert(Subsection);
-  C13Builders.push_back(llvm::make_unique<DebugSubsectionRecordBuilder>(
+  C13Builders.push_back(std::make_unique<DebugSubsectionRecordBuilder>(
       std::move(Subsection), CodeViewContainer::Pdb));
 }
 
 void DbiModuleDescriptorBuilder::addDebugSubsection(
     const DebugSubsectionRecord &SubsectionContents) {
-  C13Builders.push_back(llvm::make_unique<DebugSubsectionRecordBuilder>(
+  C13Builders.push_back(std::make_unique<DebugSubsectionRecordBuilder>(
       SubsectionContents, CodeViewContainer::Pdb));
 }