Get rid of a redundant parameter from VisiblePositionInFlatTree version of IsStartOfParagraph()

This patch gets rid of a redundant parameter from |VisiblePositionInFlatTree|
version of |IsStartOfParagraph()| since it always called with
|kCannotCrossEditingBoundary| for improving code health.

Change-Id: I366f26397c6d9a4ecb5202b4dd0e1153f52bd372
Reviewed-on: https://chromium-review.googlesource.com/714800
Reviewed-by: Xiaocheng Hu <xiaochengh@chromium.org>
Reviewed-by: Yoichi Osato <yoichio@chromium.org>
Commit-Queue: Yoshifumi Inoue <yosin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#508616}
2 files changed