Use std::make_shared in LLDB (NFC)

Unlike std::make_unique, which is only available since C++14,
std::make_shared is available since C++11. Not only is std::make_shared
a lot more readable compared to ::reset(new), it also performs a single
heap allocation for the object and control block.

Differential revision: https://reviews.llvm.org/D57990

llvm-svn: 353764
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
index 27985d0..a223130 100644
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp
@@ -6,7 +6,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include <cctype>
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTDiagnostic.h"
 #include "clang/AST/ExternalASTSource.h"
@@ -89,6 +88,9 @@
 #include "lldb/Utility/StreamString.h"
 #include "lldb/Utility/StringList.h"
 
+#include <cctype>
+#include <memory>
+
 using namespace clang;
 using namespace llvm;
 using namespace lldb_private;
@@ -1104,11 +1106,11 @@
     custom_passes.EarlyPasses->run(*llvm_module_ap);
   }
 
-  execution_unit_sp.reset(
-      new IRExecutionUnit(m_llvm_context, // handed off here
+  execution_unit_sp = std::make_shared<IRExecutionUnit>(
+      m_llvm_context, // handed off here
                           llvm_module_ap, // handed off here
                           function_name, exe_ctx.GetTargetSP(), sc,
-                          m_compiler->getTargetOpts().Features));
+      m_compiler->getTargetOpts().Features);
 
   ClangExpressionHelper *type_system_helper =
       dyn_cast<ClangExpressionHelper>(m_expr.GetTypeSystemHelper());