Notifies the IME extension for IME ready with onActivate/onFocus events at start.

chrome/browser/extensions/api/input_ime/input_ime_api.cc

 // Copyright (c) 2012 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/input_ime/input_ime_api.h"
 
 #include "base/lazy_instance.h"
 #include "chrome/common/extensions/api/input_ime.h"
 #include "extensions/browser/extension_registry.h"
 
@@ skipping 356 matching lines @@
   extension_registry_observer_.Add(ExtensionRegistry::Get(browser_context_));
 
   EventRouter* event_router = EventRouter::Get(browser_context_);
   event_router->RegisterObserver(this, input_ime::OnFocus::kEventName);
 }
 
 InputImeAPI::~InputImeAPI() {
   EventRouter::Get(browser_context_)->UnregisterObserver(this);
 }
 
+void InputImeAPI::OnListenerAdded(const EventListenerInfo& details) {
+  if (!details.browser_context)
+    return;
+  InputImeEventRouter* event_router =
+      GetInputImeEventRouter(Profile::FromBrowserContext(
+          Profile::FromBrowserContext(details.browser_context)));
+  InputMethodEngineBase* engine =
+      event_router ? event_router->GetActiveEngine(details.extension_id)
+                   : nullptr;
+
+  // Notifies the IME extension for IME ready with onActivate/onFocus events.
+  if (engine)
+    engine->Enable(engine->GetActiveComponentId());
+}
+
 static base::LazyInstance<BrowserContextKeyedAPIFactory<InputImeAPI> >
     g_factory = LAZY_INSTANCE_INITIALIZER;
 
 // static
 BrowserContextKeyedAPIFactory<InputImeAPI>* InputImeAPI::GetFactoryInstance() {
   return g_factory.Pointer();
 }
 
 InputImeEventRouter* GetInputImeEventRouter(Profile* profile) {
   if (!profile)
     return nullptr;
   if (profile->HasOffTheRecordProfile())
     profile = profile->GetOffTheRecordProfile();
   return extensions::InputImeEventRouterFactory::GetInstance()->GetRouter(
       profile);
 }
 
 }  // namespace extensions