Revert of Fix startup_metric racing condition: It used to wait t.WaitForDocumentReadyStateToBeComplete() befo… (patchset #2 id:20001 of https://codereview.chromium.org/1041213003/)
Revert of Fix startup_metric racing condition: It used to wait t.WaitForDocumentReadyStateToBeComplete() befo… (patchset #2 id:20001 of https://codereview.chromium.org/1041213003/)

Reason for revert:
Causing test failures on several bots. See crbug.com/472603

Original issue's description:
> 1. Use window.performance.timing instead of statsCollectionController to get page loading time.
> 2. Fix waiting condition to avoid racing condition
>
> BUG=467964
>
> Committed: https://crrev.com/91e201627c7dee41d085b1829b7a60daf9b9e601
> Cr-Commit-Position: refs/heads/master@{#323213}

TBR=nednguyen@google.com,cylee@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=467964

Review URL: https://codereview.chromium.org/1051813002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#323233}

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