Fix uninitialized variable compiler errors [GCC 4.8.4]

src/compiler/ast-graph-builder.cc

Index: src/compiler/ast-graph-builder.cc
diff --git a/src/compiler/ast-graph-builder.cc b/src/compiler/ast-graph-builder.cc
index 5dc28518325ddadee2249ecdc856316682d0fb5f..caf2d74254df9a9f3789b9153d65e8698e795919 100644
--- a/src/compiler/ast-graph-builder.cc
+++ b/src/compiler/ast-graph-builder.cc
@@ -2216,13 +2216,12 @@ void AstGraphBuilder::VisitThrow(Throw* expr) {
 
 
 void AstGraphBuilder::VisitProperty(Property* expr) {
-  Node* value;
+  Node* value = nullptr;
   LhsKind property_kind = Property::GetAssignType(expr);
   VectorSlotPair pair = CreateVectorSlotPair(expr->PropertyFeedbackSlot());
   switch (property_kind) {
     case VARIABLE:
       UNREACHABLE();
-      value = nullptr;
       break;
     case NAMED_PROPERTY: {
       VisitForValue(expr->obj());