Handle "//# sourceURL" comments in the Parser instead of the JS.

src/bootstrapper.cc

Index: src/bootstrapper.cc
diff --git a/src/bootstrapper.cc b/src/bootstrapper.cc
index a2d1388d403b2eecfd18f0e2901b38f0bf4e2454..3e0a27bd2752cf577ea61dd02584e56fe7cdd645 100644
--- a/src/bootstrapper.cc
+++ b/src/bootstrapper.cc
@@ -1763,7 +1763,7 @@ bool Genesis::InstallNatives() {
     native_context()->set_script_function(*script_fun);
 
     Handle<Map> script_map = Handle<Map>(script_fun->initial_map());
-    Map::EnsureDescriptorSlack(script_map, 13);
+    Map::EnsureDescriptorSlack(script_map, 14);
 
     PropertyAttributes attribs =
         static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE | READ_ONLY);
@@ -1870,6 +1870,23 @@ bool Genesis::InstallNatives() {
       script_map->AppendDescriptor(&d);
     }
 
+    Handle<AccessorInfo> script_source_url =
+        Accessors::ScriptSourceUrlInfo(isolate(), attribs);
+    {
+      CallbacksDescriptor d(Handle<Name>(Name::cast(script_source_url->name())),
+                            script_source_url, attribs);
+      script_map->AppendDescriptor(&d);
+    }
+
+    Handle<AccessorInfo> script_source_mapping_url =
+        Accessors::ScriptSourceMappingUrlInfo(isolate(), attribs);
+    {
+      CallbacksDescriptor d(
+          Handle<Name>(Name::cast(script_source_mapping_url->name())),
+          script_source_mapping_url, attribs);
+      script_map->AppendDescriptor(&d);
+    }
+
     // Allocate the empty script.
     Handle<Script> script = factory()->NewScript(factory()->empty_string());
     script->set_type(Smi::FromInt(Script::TYPE_NATIVE));