Expose native, desktop and mobile gesture detection defaults

ui/events/gesture_detection/gesture_detector.cc

Index: ui/events/gesture_detection/gesture_detector.cc
diff --git a/ui/events/gesture_detection/gesture_detector.cc b/ui/events/gesture_detection/gesture_detector.cc
index c0924488165528b3331f02052b7597d644799a32..a88546c018ca1123dc3c13edd5d7dd80f4823ae8 100644
--- a/ui/events/gesture_detection/gesture_detector.cc
+++ b/ui/events/gesture_detection/gesture_detector.cc
@@ -38,7 +38,8 @@ enum TimeoutEvent {
 }  // namespace
 
 // Note: These constants were taken directly from the default (unscaled)
-// versions found in Android's ViewConfiguration.
+// versions found in Android's ViewConfiguration. Do not change these default
+// values without explicitly consulting an OWNER.
 GestureDetector::Config::Config()
     : longpress_timeout(base::TimeDelta::FromMilliseconds(500)),
       showpress_timeout(base::TimeDelta::FromMilliseconds(180)),