Enhance chrome.app.window API with icon 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 1e30bab83f4e42725ef6e9ecc69b45b01c8a9212..fdf51c2aed657d4528761e71ab768cce4cffe34c 100644
--- a/extensions/browser/app_window/app_window.h
+++ b/extensions/browser/app_window/app_window.h
@@ -196,6 +196,9 @@ class AppWindow : public content::WebContentsDelegate,
     // the app. Defaults to false.
     bool show_in_shelf;
 
+    // Icon URL to be used for setting the window icon.
+    GURL window_icon_url;
+
     // 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;
@@ -375,6 +378,8 @@ class AppWindow : public content::WebContentsDelegate,
 
   bool show_in_shelf() const { return show_in_shelf_; }
 
+  const GURL& window_icon_url() const { return window_icon_url_; }
+
   void SetAppWindowContentsForTesting(
       std::unique_ptr<AppWindowContents> contents) {
     app_window_contents_ = std::move(contents);
@@ -580,6 +585,11 @@ class AppWindow : public content::WebContentsDelegate,
   // Whether |show_in_shelf| was set in the CreateParams.
   bool show_in_shelf_;
 
+  // Icon URL to be used for setting the window icon. If not empty,
+  // app_icon_ will be fetched and set using this URL and will have
+  // app_icon_image_ as a badge.
+  GURL window_icon_url_;
+
   // PlzNavigate: this is called when the first navigation is ready to commit.
   base::Closure on_first_commit_callback_;