Merge "webkit: add a note regarding FLAG_SECURE for default dialogs" into rvc-dev am: f7484457 am: efe6c29f am: 3aa2e1fd

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11617993

Change-Id: If824dcb356fb03e08091aa8c259b7cfe8f5f9d3f