Use Variable::binding_needs_init() to determine hole initialization

src/crankshaft/hydrogen.cc

Index: src/crankshaft/hydrogen.cc
diff --git a/src/crankshaft/hydrogen.cc b/src/crankshaft/hydrogen.cc
index d455140af9dc5342d44c8a523fa066a8e2d53087..b705c3be5eeb98593108fff89b391f7127e6beac 100644
--- a/src/crankshaft/hydrogen.cc
+++ b/src/crankshaft/hydrogen.cc
@@ -12162,9 +12162,7 @@ void HOptimizedGraphBuilder::VisitDeclarations(
 void HOptimizedGraphBuilder::VisitVariableDeclaration(
     VariableDeclaration* declaration) {
   VariableProxy* proxy = declaration->proxy();
-  VariableMode mode = declaration->mode();
   Variable* variable = proxy->var();
-  bool hole_init = mode == LET || mode == CONST;
   switch (variable->location()) {
     case VariableLocation::GLOBAL:
     case VariableLocation::UNALLOCATED: {
@@ -12177,13 +12175,13 @@ void HOptimizedGraphBuilder::VisitVariableDeclaration(
     }
     case VariableLocation::PARAMETER:
     case VariableLocation::LOCAL:
-      if (hole_init) {
+      if (variable->binding_needs_init()) {
         HValue* value = graph()->GetConstantHole();
         environment()->Bind(variable, value);
       }
       break;
     case VariableLocation::CONTEXT:
-      if (hole_init) {
+      if (variable->binding_needs_init()) {
         HValue* value = graph()->GetConstantHole();
         HValue* context = environment()->context();
         HStoreContextSlot* store = Add<HStoreContextSlot>(