Recursively call UpdateBookmarkIds with the correct index_added_at value
Recursively call UpdateBookmarkIds with the correct index_added_at value

Previously, we always called UpdateBookmarkIds for children of folders with
index_added_at = 0 rather than the actual index of the child element.

BUG=474123

TBR=sky@chromium.org

Review URL: https://codereview.chromium.org/1217443025

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#337922}

chuan9/chromium-crosswalk,chuan9/chromium-crosswalk,Just-D/chromium-1,Just-D/chromium-1,chuan9/chromium-crosswalk,Pluto-tv/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,Just-D/chromium-1,Just-D/chromium-1,Just-D/chromium-1,hgl888/chromium-crosswalk,hgl888/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,chuan9/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,Chilledheart/chromium,hgl888/chromium-crosswalk,Just-D/chromium-1,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,hgl888/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,Chilledheart/chromium,Pluto-tv/chromium-crosswalk,Chilledheart/chromium,Pluto-tv/chromium-crosswalk,chuan9/chromium-crosswalk,axinging/chromium-crosswalk,Just-D/chromium-1,axinging/chromium-crosswalk,chuan9/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Chilledheart/chromium,Chilledheart/chromium,axinging/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Pluto-tv/chromium-crosswalk,chuan9/chromium-crosswalk,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Pluto-tv/chromium-crosswalk,chuan9/chromium-crosswalk,Chilledheart/chromium,hgl888/chromium-crosswalk,Chilledheart/chromium