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

chrome/android/java/src/org/chromium/chrome/browser/fullscreen/FullscreenHtmlApiHandler.java

Index: chrome/android/java/src/org/chromium/chrome/browser/fullscreen/FullscreenHtmlApiHandler.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/fullscreen/FullscreenHtmlApiHandler.java b/chrome/android/java/src/org/chromium/chrome/browser/fullscreen/FullscreenHtmlApiHandler.java
index 7c6e1ac298b3bed19026e687ec03c27e300830e6..41ea156aba4aea743ea54eed0fbbf335ae96dd79 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/fullscreen/FullscreenHtmlApiHandler.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/fullscreen/FullscreenHtmlApiHandler.java
@@ -18,6 +18,7 @@ import android.view.Window;
 import android.view.WindowManager;
 
 import org.chromium.chrome.R;
+import org.chromium.chrome.browser.ChromeFeatureList;
 import org.chromium.chrome.browser.preferences.website.ContentSetting;
 import org.chromium.chrome.browser.preferences.website.FullscreenInfo;
 import org.chromium.chrome.browser.tab.Tab;
@@ -309,7 +310,9 @@ public class FullscreenHtmlApiHandler {
         mTabInFullscreen = tab;
         FullscreenInfo fullscreenInfo = new FullscreenInfo(tab.getUrl(), null, tab.isIncognito());
         ContentSetting fullscreenPermission = fullscreenInfo.getContentSetting();
-        if (fullscreenPermission != ContentSetting.ALLOW) {
+        // In simplified fullscreen mode, do not show the infobar (always allow). The toast will
+        // still be shown.
+        if (fullscreenPermission != ContentSetting.ALLOW && !isSimplifiedFullscreenUIEnabled()) {
             mFullscreenInfoBarDelegate = FullscreenInfoBarDelegate.create(this, tab);
         }
     }
@@ -379,4 +382,8 @@ public class FullscreenHtmlApiHandler {
         }
         return flags;
     }
+
+    private static boolean isSimplifiedFullscreenUIEnabled() {
+        return ChromeFeatureList.isEnabled("ViewsSimplifiedFullscreenUI");
+    }
 }