[optimizing] Name the last DCE pass.

This will allow Checker to differentiate between them.

Change-Id: I972d452a64f1c19d370567b9ef3d620f9b835a9a
diff --git a/compiler/optimizing/constant_folding_test.cc b/compiler/optimizing/constant_folding_test.cc
index e420a62..02ad675 100644
--- a/compiler/optimizing/constant_folding_test.cc
+++ b/compiler/optimizing/constant_folding_test.cc
@@ -62,7 +62,7 @@
 
   check_after_cf(graph);
 
-  HDeadCodeElimination(graph, nullptr).Run();
+  HDeadCodeElimination(graph).Run();
   SSAChecker ssa_checker_dce(&allocator, graph);
   ssa_checker_dce.Run();
   ASSERT_TRUE(ssa_checker_dce.IsValid());
diff --git a/compiler/optimizing/dead_code_elimination.h b/compiler/optimizing/dead_code_elimination.h
index 3f309c5..cee9364 100644
--- a/compiler/optimizing/dead_code_elimination.h
+++ b/compiler/optimizing/dead_code_elimination.h
@@ -29,8 +29,10 @@
  */
 class HDeadCodeElimination : public HOptimization {
  public:
-  HDeadCodeElimination(HGraph* graph, OptimizingCompilerStats* stats)
-      : HOptimization(graph, true, kDeadCodeEliminationPassName, stats) {}
+  HDeadCodeElimination(HGraph* graph,
+                       OptimizingCompilerStats* stats = nullptr,
+                       const char* name = kDeadCodeEliminationPassName)
+      : HOptimization(graph, true, name, stats) {}
 
   void Run() OVERRIDE;
 
diff --git a/compiler/optimizing/dead_code_elimination_test.cc b/compiler/optimizing/dead_code_elimination_test.cc
index 6350019..98ae1ec 100644
--- a/compiler/optimizing/dead_code_elimination_test.cc
+++ b/compiler/optimizing/dead_code_elimination_test.cc
@@ -44,7 +44,7 @@
   std::unique_ptr<const X86InstructionSetFeatures> features_x86(
       X86InstructionSetFeatures::FromCppDefines());
   x86::CodeGeneratorX86 codegenX86(graph, *features_x86.get(), CompilerOptions());
-  HDeadCodeElimination(graph, nullptr).Run();
+  HDeadCodeElimination(graph).Run();
   SSAChecker ssa_checker(&allocator, graph);
   ssa_checker.Run();
   ASSERT_TRUE(ssa_checker.IsValid());
diff --git a/compiler/optimizing/optimizing_compiler.cc b/compiler/optimizing/optimizing_compiler.cc
index ab752c3..218894f 100644
--- a/compiler/optimizing/optimizing_compiler.cc
+++ b/compiler/optimizing/optimizing_compiler.cc
@@ -321,7 +321,7 @@
                              PassInfoPrinter* pass_info_printer,
                              StackHandleScopeCollection* handles) {
   HDeadCodeElimination dce1(graph, stats);
-  HDeadCodeElimination dce2(graph, stats);
+  HDeadCodeElimination dce2(graph, stats, "dead_code_elimination_final");
   HConstantFolding fold1(graph);
   InstructionSimplifier simplify1(graph, stats);
   HBooleanSimplifier boolean_not(graph);