Makes the InputMethodEngine can be switched per profile when the top-level browser window is switch…

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

 // Copyright 2015 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.
 
 // This file is for non-chromeos (win & linux) functions, such as
 // chrome.input.ime.activate, chrome.input.ime.createWindow and
 // chrome.input.ime.onSelectionChanged.
 // TODO(azurewei): May refactor the code structure by using delegate or
 // redesign the API to remove this platform-specific file in the future.
 
@@ skipping 73 matching lines @@
     }
 
     std::unique_ptr<base::ListValue> args(
         OnCompositionBoundsChanged::Create(bounds_list));
 
     DispatchEventToExtension(
         extensions::events::INPUT_IME_ON_COMPOSITION_BOUNDS_CHANGED,
         OnCompositionBoundsChanged::kEventName, std::move(args));
   }
 
+  void OnRequestEngineSwitch() override {
+    Browser* browser = chrome::FindLastActive();
+    if (!browser)
+      return;
+    extensions::InputImeEventRouter* router =
+        extensions::GetInputImeEventRouter(browser->profile());
+    if (!router)
+      return;
+    ui::IMEBridge::Get()->SetCurrentEngineHandler(router->active_engine());
+  }
+
  private:
   // ImeObserver overrides.
   void DispatchEventToExtension(
       extensions::events::HistogramValue histogram_value,
       const std::string& event_name,
       std::unique_ptr<base::ListValue> args) override {
     if (!IsInputImeEnabled()) {
       return;
     }
 
@@ skipping 294 matching lines @@
     return RespondNow(Error(kErrorNoActiveEngine));
 
   std::unique_ptr<api::input_ime::HideWindow::Params> params(
       api::input_ime::HideWindow::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
   engine->HideImeWindow(params->window_id);
   return RespondNow(NoArguments());
 }
 
 }  // namespace extensions