Refactor Select-to-speak so that mouse events are forwarded to the extension.

chrome/browser/extensions/api/automation_internal/automation_internal_api.cc

 // Copyright 2014 The Chromium 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 "chrome/browser/extensions/api/automation_internal/automation_internal_api.h"
 
 #include <stdint.h>
 
 #include <memory>
 #include <vector>
@@ skipping 397 matching lines @@
   std::unique_ptr<Params> params(Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   ui::AXTreeIDRegistry* registry = ui::AXTreeIDRegistry::GetInstance();
   ui::AXHostDelegate* delegate =
       registry->GetHostDelegate(params->args.tree_id);
   if (delegate) {
 #if defined(USE_AURA)
     ui::AXActionData data;
     ConvertToAXActionData(params.get(), &data);
     delegate->PerformAction(data);
+    return RespondNow(NoArguments());
 #else
     NOTREACHED();
     return RespondNow(Error("Unexpected action on desktop automation tree;"
                             " platform does not support desktop automation"));
 #endif  // defined(USE_AURA)
   }
   content::RenderFrameHost* rfh =
       content::RenderFrameHost::FromAXTreeID(params->args.tree_id);
   if (!rfh)
     return RespondNow(Error("Ignoring action on destroyed node"));
@@ skipping 96 matching lines @@
     int result_acc_obj_id) {
   if (!error.empty()) {
     Respond(Error(error));
     return;
   }
 
   Respond(OneArgument(base::MakeUnique<base::Value>(result_acc_obj_id)));
 }
 
 }  // namespace extensions