[Parser] Don't internalize on-the-fly.

test/cctest/asmjs/test-asm-typer.cc

Index: test/cctest/asmjs/test-asm-typer.cc
diff --git a/test/cctest/asmjs/test-asm-typer.cc b/test/cctest/asmjs/test-asm-typer.cc
index dcb778533dcf5767bb7e205420fd51fe3526c82b..83826a704ad7cbbddc00f9e054614dc6f910822b 100644
--- a/test/cctest/asmjs/test-asm-typer.cc
+++ b/test/cctest/asmjs/test-asm-typer.cc
@@ -276,6 +276,7 @@ class AsmTyperHarnessBuilder {
  private:
   Variable* DeclareVariable(VariableName var_name) {
     auto* name_ast_string = ast_value_factory_.GetOneByteString(var_name.name_);
+    ast_value_factory_.Internalize(isolate_);
     return var_name.mode_ == DYNAMIC_GLOBAL
                ? outer_scope_->DeclareDynamicGlobal(name_ast_string,
                                                     Variable::NORMAL)