Remove extension group from DOMWrapperWorld.

extensions/renderer/extension_frame_helper.cc

Index: extensions/renderer/extension_frame_helper.cc
diff --git a/extensions/renderer/extension_frame_helper.cc b/extensions/renderer/extension_frame_helper.cc
index 5d3709e4fadc7d55b977087e060a60bb988149a9..91d38c3fe63d57d3a2bf26e1b37a85b9c88d1555 100644
--- a/extensions/renderer/extension_frame_helper.cc
+++ b/extensions/renderer/extension_frame_helper.cc
@@ -198,18 +198,16 @@ void ExtensionFrameHelper::DidStartProvisionalLoad() {
   v8::Local<v8::Context> context =
       render_frame()->GetWebFrame()->mainWorldScriptContext();
   v8::Context::Scope context_scope(context);
-  extension_dispatcher_->DidCreateScriptContext(
-      render_frame()->GetWebFrame(), context, 0, 0);
+  extension_dispatcher_->DidCreateScriptContext(render_frame()->GetWebFrame(),
+                                                context, 0);
   // TODO(devlin): Add constants for main world id, no extension group.
 }
 
 void ExtensionFrameHelper::DidCreateScriptContext(
     v8::Local<v8::Context> context,
-    int extension_group,
     int world_id) {
   if (context == render_frame()->GetWebFrame()->mainWorldScriptContext() &&
       render_frame()->IsBrowserSideNavigationPending()) {
-    DCHECK_EQ(0, extension_group);
     DCHECK_EQ(0, world_id);
     DCHECK(!delayed_main_world_script_initialization_);
     // Defer initializing the extensions script context now because it depends
@@ -217,8 +215,8 @@ void ExtensionFrameHelper::DidCreateScriptContext(
     // point with PlzNavigate.
     delayed_main_world_script_initialization_ = true;
   } else {
-    extension_dispatcher_->DidCreateScriptContext(
-        render_frame()->GetWebFrame(), context, extension_group, world_id);
+    extension_dispatcher_->DidCreateScriptContext(render_frame()->GetWebFrame(),
+                                                  context, world_id);
   }
 }