[debug,api] Do not use embedder field for debug context id.

src/runtime/runtime-function.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/runtime/runtime-utils.h"
 
 #include "src/accessors.h"
 #include "src/arguments.h"
 #include "src/compiler.h"
 #include "src/frames-inl.h"
@@ skipping 93 matching lines @@
   CONVERT_ARG_CHECKED(JSFunction, fun, 0);
   int pos = fun->shared()->start_position();
   return Smi::FromInt(pos);
 }
 
 RUNTIME_FUNCTION(Runtime_FunctionGetContextData) {
   SealHandleScope shs(isolate);
   DCHECK_EQ(1, args.length());
 
   CONVERT_ARG_CHECKED(JSFunction, fun, 0);
-  FixedArray* array = fun->native_context()->embedder_data();
-  return array->get(v8::Context::kDebugIdIndex);
+  return fun->native_context()->debug_context_id();
 }
 
 RUNTIME_FUNCTION(Runtime_FunctionSetInstanceClassName) {
   SealHandleScope shs(isolate);
   DCHECK_EQ(2, args.length());
 
   CONVERT_ARG_CHECKED(JSFunction, fun, 0);
   CONVERT_ARG_CHECKED(String, name, 1);
   fun->shared()->set_instance_class_name(name);
   return isolate->heap()->undefined_value();
@@ skipping 180 matching lines @@
   DCHECK_EQ(1, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSReceiver, function, 0);
   return function->IsJSBoundFunction()
              ? *JSBoundFunction::ToString(
                    Handle<JSBoundFunction>::cast(function))
              : *JSFunction::ToString(Handle<JSFunction>::cast(function));
 }
 
 }  // namespace internal
 }  // namespace v8