[LLDB] 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.

Differential revision: https://reviews.llvm.org/D66259

llvm-svn: 368933
diff --git a/lldb/tools/lldb-test/lldb-test.cpp b/lldb/tools/lldb-test/lldb-test.cpp
index e522f94..8d0ef68 100644
--- a/lldb/tools/lldb-test/lldb-test.cpp
+++ b/lldb/tools/lldb-test/lldb-test.cpp
@@ -969,7 +969,7 @@
 
   SystemLifetimeManager DebuggerLifetime;
   if (auto e = DebuggerLifetime.Initialize(
-          llvm::make_unique<SystemInitializerTest>(), nullptr)) {
+          std::make_unique<SystemInitializerTest>(), nullptr)) {
     WithColor::error() << "initialization failed: " << toString(std::move(e))
                        << '\n';
     return 1;