Allow component IME extension use app.window and add 'ime' window type for app window

extensions/browser/app_window/app_window.h

Index: extensions/browser/app_window/app_window.h
diff --git a/extensions/browser/app_window/app_window.h b/extensions/browser/app_window/app_window.h
index f3b8e6ecbc4fbd9682f599b3a9954002dc86a676..73f413e017e1dd75c83a06abfa377960d350c7c0 100644
--- a/extensions/browser/app_window/app_window.h
+++ b/extensions/browser/app_window/app_window.h
@@ -150,6 +150,7 @@ class AppWindow : public content::NotificationObserver,
     SkColor active_frame_color;
     SkColor inactive_frame_color;
     bool alpha_enabled;
+    bool is_ime_window;
 
     // The initial content/inner bounds specification (excluding any window
     // decorations).
@@ -347,6 +348,9 @@ class AppWindow : public content::NotificationObserver,
     app_window_contents_ = contents.Pass();
   }
 
+  // Whether the app window is an ime window.
+  bool is_ime_window() const { return is_ime_window_; }
+
  protected:
   virtual ~AppWindow();
 
@@ -547,6 +551,9 @@ class AppWindow : public content::NotificationObserver,
   // Whether |alpha_enabled| was set in the CreateParams.
   bool requested_alpha_enabled_;
 
+  // Whether |ime| was set in the CreateParams.
+  bool is_ime_window_;
+
   DISALLOW_COPY_AND_ASSIGN(AppWindow);
 };