GitLab

Created |UpdateCustomWallpaperLayout| so that |SetWallpaperInfo| is
made private. Also, WallpaperManager::UpdateWallpaper can be deprecated
due to this CL and the previous CL.

Bug: 779221
Change-Id: I27ec8095e0ca21eee8bea3216b930d9bef9e4f4e
Reviewed-on: https://chromium-review.googlesource.com/828696Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Commit-Queue: Wenzhao (Colin) Zang <wzang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#527045}