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

chrome/common/extensions/api/app_window.idl

Index: chrome/common/extensions/api/app_window.idl
diff --git a/chrome/common/extensions/api/app_window.idl b/chrome/common/extensions/api/app_window.idl
index caff663e29def5edda094f0f520ba3571bbe3072..7e52b608e22227e504226a726f3e74ceea4419a5 100644
--- a/chrome/common/extensions/api/app_window.idl
+++ b/chrome/common/extensions/api/app_window.idl
@@ -215,6 +215,12 @@ namespace app.window {
     // Type of window to create.
     [nodoc] WindowType? type;
 
+    // Creates a special ime window. This window is not focusable and can be
+    // stacked above virtual keyboard window. This is restriced to component ime
+    // extensions.
+    // Requires app.window.ime API permission.
+    [nodoc] boolean? ime;
+
     // 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