Fix observer hanging after shudown because the sign in popup was not dismissed.
Fix observer hanging after shudown because the sign in popup was not dismissed.

This only happens in real sync server integration tests. The fix adds a call to SyncConfirmationUIClosed() after sync setup completion. The call deletes any observer owned by OneClickSigninSyncStarter object.

BUG=484388

Review URL: https://codereview.chromium.org/1120393002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#328566}

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