Enhance chrome.app.window API with title property

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 fdf51c2aed657d4528761e71ab768cce4cffe34c..a30fbc3459f9714aa494074aabcff1d1a1cb1f92 100644
--- a/extensions/browser/app_window/app_window.h
+++ b/extensions/browser/app_window/app_window.h
@@ -199,6 +199,9 @@ class AppWindow : public content::WebContentsDelegate,
     // Icon URL to be used for setting the window icon.
     GURL window_icon_url;
 
+    // Title of the window that has its own icon in the shelf.
+    std::string title;
+
     // The API enables developers to specify content or window bounds. This
     // function combines them into a single, constrained window size.
     gfx::Rect GetInitialWindowBounds(const gfx::Insets& frame_insets) const;
@@ -380,6 +383,8 @@ class AppWindow : public content::WebContentsDelegate,
 
   const GURL& window_icon_url() const { return window_icon_url_; }
 
+  const std::string& title() const { return title_; }
+
   void SetAppWindowContentsForTesting(
       std::unique_ptr<AppWindowContents> contents) {
     app_window_contents_ = std::move(contents);
@@ -590,6 +595,9 @@ class AppWindow : public content::WebContentsDelegate,
   // app_icon_image_ as a badge.
   GURL window_icon_url_;
 
+  // Title of the window that has its own icon in the shelf.
+  std::string title_;
+
   // PlzNavigate: this is called when the first navigation is ready to commit.
   base::Closure on_first_commit_callback_;