Refactor all instances of `typedef y x` to the C++11 `using x = y` syntax.

src/IceSwitchLowering.h

 //===- subzero/src/IceSwitchLowering.h - Switch lowering --------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
 /// \brief The file contains helpers for switch lowering.
 //===----------------------------------------------------------------------===//
 
 #ifndef SUBZERO_SRC_ICESWITCHLOWERING_H
 #define SUBZERO_SRC_ICESWITCHLOWERING_H
 
 #include "IceDefs.h"
 
 namespace Ice {
 
 class CaseCluster;
 
-typedef std::vector<CaseCluster, CfgLocalAllocator<CaseCluster>>
-    CaseClusterArray;
+using CaseClusterArray =
+    std::vector<CaseCluster, CfgLocalAllocator<CaseCluster>>;
 
 /// A cluster of cases can be tested by a common method during switch lowering.
 class CaseCluster {
   CaseCluster() = delete;
 
 public:
   enum CaseClusterKind {
     Range,     /// Numerically adjacent case values with same target.
     JumpTable, /// Different targets and possibly sparse.
   };
@@ skipping 67 matching lines @@
   IceString FuncName;
   SizeT Id;
   std::vector<intptr_t> TargetOffsets;
 };
 
 using JumpTableDataList = std::vector<JumpTableData>;
 
 } // end of namespace Ice
 
 #endif //  SUBZERO_SRC_ICESWITCHLOWERING_H