Subzero: Change llvm::OwningPtr to C++11's std::unique_ptr.

While I'm at it, normalize the #include order:

1. C++ library headers
2. LLVM headers
3. Subzero headers

A blank line between each group.  Each group sorted alphabetically, case-insensitive.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3930
R=jfb@chromium.org, jvoung@chromium.org

Review URL: https://codereview.chromium.org/622443002
diff --git a/src/IceTranslator.cpp b/src/IceTranslator.cpp
index 91dcfd4..9cc97a0 100644
--- a/src/IceTranslator.cpp
+++ b/src/IceTranslator.cpp
@@ -12,16 +12,18 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include <iostream>
+#include <memory>
+
+#include "llvm/IR/Constant.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Module.h"
+
 #include "IceCfg.h"
 #include "IceClFlags.h"
 #include "IceDefs.h"
 #include "IceTargetLowering.h"
 #include "IceTranslator.h"
-#include "llvm/IR/Module.h"
-#include "llvm/IR/Constant.h"
-#include "llvm/IR/Constants.h"
-
-#include <iostream>
 
 using namespace Ice;
 
@@ -96,7 +98,7 @@
 }
 
 void Translator::convertGlobals(llvm::Module *Mod) {
-  llvm::OwningPtr<TargetGlobalInitLowering> GlobalLowering(
+  std::unique_ptr<TargetGlobalInitLowering> GlobalLowering(
       TargetGlobalInitLowering::createLowering(Ctx->getTargetArch(), Ctx));
   for (llvm::Module::const_global_iterator I = Mod->global_begin(),
                                            E = Mod->global_end();