Add policy for fullscreen mode; disallow fullscreen in public sessions

chrome/browser/ui/fullscreen/fullscreen_controller.cc

Index: chrome/browser/ui/fullscreen/fullscreen_controller.cc
diff --git a/chrome/browser/ui/fullscreen/fullscreen_controller.cc b/chrome/browser/ui/fullscreen/fullscreen_controller.cc
index 7c1621e0a32673e73d50ff51c71ef71a61af55d4..d275cfe69950c57cab05096e8fadd071daea269c 100644
--- a/chrome/browser/ui/fullscreen/fullscreen_controller.cc
+++ b/chrome/browser/ui/fullscreen/fullscreen_controller.cc
@@ -28,6 +28,9 @@
 
 #if defined(OS_MACOSX)
 #include "base/mac/mac_util.h"
+#else
+#include "base/prefs/pref_service.h"
+#include "chrome/common/pref_names.h"
 #endif
 
 using content::RenderViewHost;
@@ -552,6 +555,16 @@ void FullscreenController::ToggleFullscreenModeInternal(
   if (chrome::IsRunningInAppMode() && window_->IsFullscreen())
     return;
 
+#if !defined(OS_MACOSX)
+  // Do not enter fullscreen mode if disallowed by pref. This prevents the user
+  // from manually entering fullscreen mode and also disables kiosk mode on
+  // desktop platforms.
+  if (enter_fullscreen &&
+      !profile_->GetPrefs()->GetBoolean(prefs::kFullscreenAllowed)) {
+    return;
+  }
+#endif
+
   if (enter_fullscreen)
     EnterFullscreenModeInternal(option);
   else