Allow full-screen mode when not connected, and remember the previous setting.

remoting/webapp/crd/html/window_frame.css

Index: remoting/webapp/crd/html/window_frame.css
diff --git a/remoting/webapp/crd/html/window_frame.css b/remoting/webapp/crd/html/window_frame.css
index 857f40c25095f026cf605896a45540d06121a9a4..616dc00ce5186610eacffc4db507647faaaa98f7 100644
--- a/remoting/webapp/crd/html/window_frame.css
+++ b/remoting/webapp/crd/html/window_frame.css
@@ -122,10 +122,8 @@ html.apps-v2 .window-body {
   border-right: none;
 }
 
-/* The Disconnect, full-screen and options buttons are only displayed when
-   connected. */
+/* The Disconnect and options buttons are only displayed when connected. */
 body:not(.connected) .window-disconnect,
-body:not(.connected) .window-fullscreen,
 body:not(.connected) .window-options {
   display: none;
 }