[iOS] Add experimental new keyboard accessory view.

ios/chrome/browser/experimental_flags.mm

Index: ios/chrome/browser/experimental_flags.mm
diff --git a/ios/chrome/browser/experimental_flags.mm b/ios/chrome/browser/experimental_flags.mm
index 6dd6b82a2cf2fd3bde43c4bb8face7f65ab57f1e..e19d040b2a8a27599f250e2b72d6fd8279005959 100644
--- a/ios/chrome/browser/experimental_flags.mm
+++ b/ios/chrome/browser/experimental_flags.mm
@@ -277,4 +277,9 @@ bool IsNewFeedbackKitEnabled() {
       boolForKey:@"NewFeedbackKitEnabled"];
 }
 
+bool IsKeyboardAccessoryViewWithCameraSearchEnabled() {
+  return [[NSUserDefaults standardUserDefaults]
+      boolForKey:@"NewKeyboardAccessoryViewEnabled"];
+}
+
 }  // namespace experimental_flags