Update ash to use new devtools base agent

ash/common/wm_shell.cc

Index: ash/common/wm_shell.cc
diff --git a/ash/common/wm_shell.cc b/ash/common/wm_shell.cc
index da3bb1d99889a48445bfe23ebbe7ec003e9ff701..ddaa892d93c09415c9100354e84b43a4f09b75c6 100644
--- a/ash/common/wm_shell.cc
+++ b/ash/common/wm_shell.cc
@@ -9,7 +9,7 @@
 #include "ash/common/accelerators/accelerator_controller.h"
 #include "ash/common/accelerators/ash_focus_manager_factory.h"
 #include "ash/common/accessibility_delegate.h"
-#include "ash/common/devtools/devtools_dom_agent.h"
+#include "ash/common/devtools/ash_devtools_dom_agent.h"
 #include "ash/common/focus_cycler.h"
 #include "ash/common/keyboard/keyboard_ui.h"
 #include "ash/common/new_window_client_proxy.h"
@@ -93,7 +93,7 @@ void WmShell::Initialize(const scoped_refptr<base::SequencedWorkerPool>& pool) {
     auto dom_backend = base::MakeUnique<devtools::AshDevToolsDOMAgent>(this);
     auto devtools_client = base::MakeUnique<ui::devtools::UiDevToolsClient>(
         "Ash", devtools_server_.get());
-    devtools_client->AddDOMBackend(std::move(dom_backend));
+    devtools_client->AddAgent(std::move(dom_backend));
     devtools_server_->AttachClient(std::move(devtools_client));
   }
 }