Introduce worker_devtools_agent_route_id for EmbeddedWorker.

content/browser/service_worker/embedded_worker_registry.cc

Index: content/browser/service_worker/embedded_worker_registry.cc
diff --git a/content/browser/service_worker/embedded_worker_registry.cc b/content/browser/service_worker/embedded_worker_registry.cc
index 249eab082b21ce3100114299d1da2811217b671b..a36cb187e505d052003b2c4b5b57b5b6839b1b19 100644
--- a/content/browser/service_worker/embedded_worker_registry.cc
+++ b/content/browser/service_worker/embedded_worker_registry.cc
@@ -5,6 +5,7 @@
 #include "content/browser/service_worker/embedded_worker_registry.h"
 
 #include "base/stl_util.h"
+#include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/service_worker/embedded_worker_instance.h"
 #include "content/browser/service_worker/service_worker_context_core.h"
 #include "content/common/service_worker/embedded_worker_messages.h"
@@ -30,11 +31,17 @@ ServiceWorkerStatusCode EmbeddedWorkerRegistry::StartWorker(
     int embedded_worker_id,
     int64 service_worker_version_id,
     const GURL& scope,
-    const GURL& script_url) {
+    const GURL& script_url,
+    int* worker_devtools_agent_route_id) {
+  *worker_devtools_agent_route_id =
+      RenderProcessHostImpl::GetNextRoutingIDForProcess(process_id);
   return Send(
       process_id,
-      new EmbeddedWorkerMsg_StartWorker(
-          embedded_worker_id, service_worker_version_id, scope, script_url));
+      new EmbeddedWorkerMsg_StartWorker(embedded_worker_id,
+                                        service_worker_version_id,
+                                        scope,
+                                        script_url,
+                                        *worker_devtools_agent_route_id));
 }
 
 ServiceWorkerStatusCode EmbeddedWorkerRegistry::StopWorker(