Rename UsbPrinterNotificationController::IsNotification

Rename IsNotification to IsNotificationDisplayed to more clearly
convey the functionality.

Change-Id: I4cfa84b8211b016f9ea867263080deb230e83c6d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1621356
Auto-Submit: Bailey Berro <baileyberro@chromium.org>
Commit-Queue: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661716}
4 files changed