Refactored code to allow associating workers with multiple renderers.

chrome/renderer/webworker_proxy.cc

Index: chrome/renderer/webworker_proxy.cc
diff --git a/chrome/renderer/webworker_proxy.cc b/chrome/renderer/webworker_proxy.cc
index fdcc9f1d0dc55b2be736363c66743d75a5ea2f1e..553a3ac4241cb9eaa5dfdf1917ef1b491ac55a08 100644
--- a/chrome/renderer/webworker_proxy.cc
+++ b/chrome/renderer/webworker_proxy.cc
@@ -22,8 +22,10 @@ WebWorkerProxy::WebWorkerProxy(
     WebWorkerClient* client,
     ChildThread* child_thread,
     int render_view_route_id)
-    : WebWorkerBase(child_thread, MSG_ROUTING_NONE, render_view_route_id),
+    : WebWorkerBase(child_thread, 0, MSG_ROUTING_NONE, render_view_route_id),
       client_(client) {
+  // TODO(atwilson): Change to pass in a real document_id when we support nested
+  // workers.
 }
 
 WebWorkerProxy::~WebWorkerProxy() {