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..145f7f63101e81fbc76fe7238b4216351d99115b 100644
--- a/chrome/browser/ui/fullscreen/fullscreen_controller.cc
+++ b/chrome/browser/ui/fullscreen/fullscreen_controller.cc
@@ -7,6 +7,7 @@
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
+#include "base/prefs/pref_service.h"
 #include "chrome/browser/app_mode/app_mode_utils.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
@@ -18,6 +19,7 @@
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension.h"
+#include "chrome/common/pref_names.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_service.h"
@@ -552,6 +554,12 @@ void FullscreenController::ToggleFullscreenModeInternal(
   if (chrome::IsRunningInAppMode() && window_->IsFullscreen())
     return;
 
+  // Do not enter fullscreen mode if disallowed by pref.
+  if (enter_fullscreen &&
+      !profile_->GetPrefs()->GetBoolean(prefs::kAllowFullscreen)) {
+    return;
+  }
+
   if (enter_fullscreen)
     EnterFullscreenModeInternal(option);
   else