Android: Remove the prompt when entering fullscreen mode (behind flag).

chrome/browser/android/chrome_feature_list.cc

Index: chrome/browser/android/chrome_feature_list.cc
diff --git a/chrome/browser/android/chrome_feature_list.cc b/chrome/browser/android/chrome_feature_list.cc
index 8b44469b7a37e05546fa58c7666eef0a6fce1ec9..fb8d15bdfa47eeff984c98698afc55dd5f0e09b7 100644
--- a/chrome/browser/android/chrome_feature_list.cc
+++ b/chrome/browser/android/chrome_feature_list.cc
@@ -11,6 +11,7 @@
 #include "base/android/jni_string.h"
 #include "base/feature_list.h"
 #include "base/macros.h"
+#include "chrome/common/chrome_features.h"
 #include "jni/ChromeFeatureList_jni.h"
 
 using base::android::ConvertJavaStringToUTF8;
@@ -26,6 +27,7 @@ namespace {
 const base::Feature* kFeaturesExposedToJava[] = {
     &kNTPOfflinePagesFeature,
     &kPhysicalWebFeature,
+    &features::kSimplifiedFullscreenUI,
 };
 
 }  // namespace