Enhance chrome.app.window API with better shelf integration

extensions/common/api/app_window.idl

Index: extensions/common/api/app_window.idl
diff --git a/extensions/common/api/app_window.idl b/extensions/common/api/app_window.idl
index f75978ec2688f6bf9c394d7e99f461214023fdd8..105b4a3afcbcab08d025740eaad769e1f81a525d 100644
--- a/extensions/common/api/app_window.idl
+++ b/extensions/common/api/app_window.idl
@@ -225,6 +225,10 @@ namespace app.window {
     // Requires the <code>app.window.ime</code> API permission.
     [nodoc] boolean? ime;
 
+    // If true, the window will have its own icon in the shelf instead of being
+    // folded in the menu of the parent app. Defaults to false.
+    boolean? showInShelf;
+
     // Frame type: <code>none</code> or <code>chrome</code> (defaults to
     // <code>chrome</code>). For <code>none</code>, the
     // <code>-webkit-app-region</code> CSS property can be used to apply