Improve handling of unary plus.

src/ia32/full-codegen-ia32.cc

Index: src/ia32/full-codegen-ia32.cc
diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index 19989b1c626dd3ea85f6cb9c3c44d7bfab8dffa9..a35f12d8cce1c495c0d7647b84de29be177c8bd1 100644
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -3967,18 +3967,6 @@ void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
       break;
     }
 
-    case Token::ADD: {
-      Comment cmt(masm_, "[ UnaryOperation (ADD)");
-      VisitForAccumulatorValue(expr->expression());
-      Label no_conversion;
-      __ JumpIfSmi(result_register(), &no_conversion);
-      ToNumberStub convert_stub;
-      __ CallStub(&convert_stub);
-      __ bind(&no_conversion);
-      context()->Plug(result_register());
-      break;
-    }
-
     case Token::SUB:
       EmitUnaryOperation(expr, "[ UnaryOperation (SUB)");
       break;