Add flag for enabling/disabling video fullscreen detection

chrome/browser/chrome_content_browser_client.cc

Index: chrome/browser/chrome_content_browser_client.cc
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index 4c471bea5ad13cdb186f88e59fc9d118a5703e1f..8061a8ae7be90533e331e1789e1f8b81f8664fcc 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -247,6 +247,7 @@
 #elif defined(OS_LINUX)
 #include "chrome/browser/chrome_browser_main_linux.h"
 #elif defined(OS_ANDROID)
+#include "chrome/browser/android/app_hooks_helper.h"
 #include "chrome/browser/chrome_browser_main_android.h"
 #include "chrome/common/descriptors_android.h"
 #include "components/crash/content/browser/crash_dump_manager_android.h"
@@ -2681,6 +2682,11 @@ void ChromeContentBrowserClient::OverrideWebkitPrefs(
       }
     }
   }
+
+  if (!command_line->HasSwitch(switches::kDisableVideoFullscreenDetection)) {
+    web_prefs->video_fullscreen_detection_enabled =
+        chrome::android::AppHooksHelper::ShouldDetectVideoFullscreen();
+  }
 #endif  // defined(OS_ANDROID)
 
   for (size_t i = 0; i < extra_parts_.size(); ++i)