[builtins] Also simplify the Symbol constructor.

src/bootstrapper.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/bootstrapper.h"
 
 #include "src/accessors.h"
 #include "src/api-natives.h"
 #include "src/base/utils/random-number-generator.h"
 #include "src/code-stubs.h"
@@ skipping 1129 matching lines @@
       AccessorConstantDescriptor d(factory->length_string(), string_length,
                                    attribs);
       string_map->AppendDescriptor(&d);
     }
   }
 
   {
     // --- S y m b o l ---
     Handle<JSFunction> symbol_fun = InstallFunction(
         global, "Symbol", JS_VALUE_TYPE, JSValue::kSize,
-        isolate->initial_object_prototype(), Builtins::kIllegal);
+        isolate->initial_object_prototype(), Builtins::kSymbolConstructor);
+    symbol_fun->shared()->set_construct_stub(isolate->builtins()->builtin(
+        Builtins::kSymbolConstructor_ConstructStub));
+    symbol_fun->shared()->set_internal_formal_parameter_count(1);
+    symbol_fun->shared()->set_length(1);
     native_context()->set_symbol_function(*symbol_fun);
   }
 
   {  // --- D a t e ---
     // Builtin functions for Date.prototype.
     InstallFunction(global, "Date", JS_DATE_TYPE, JSDate::kSize,
                     isolate->initial_object_prototype(), Builtins::kIllegal);
   }
 
 
@@ skipping 2065 matching lines @@
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   DCHECK(!IsActive());
 }
 
 }  // namespace internal
 }  // namespace v8