Revert of Map WebURLRequest::RequestContextPlugin to RESOURCE_TYPE_OBJECT. (patchset #6 id:600001 of https://codereview.chromium.org/630973002/)
Revert of Map WebURLRequest::RequestContextPlugin to RESOURCE_TYPE_OBJECT. (patchset #6 id:600001 of https://codereview.chromium.org/630973002/)

Reason for revert:
Speculative revert since it might cause browser test PDFExtensionTest.BasicPlugin to fail.

http://build.chromium.org/p/chromium.webkit/builders/Linux%20Tests%20(dbg)/builds/4962
http://build.chromium.org/p/chromium.webkit/builders/Mac10.8%20Tests/builds/11223
http://build.chromium.org/p/chromium.webkit/builders/Win7%20Tests/builds/7530

Original issue's description:
> Map WebURLRequest::RequestContextPlugin to RESOURCE_TYPE_OBJECT.
>
> The WebRequest API should treat both object requests, and requests made
> from those objects (e.g. Flash requesting an .mp4 resource) as type
> Object. We used to do this, then I broke it. :( Now I'm fixing it. :)
>
> BUG=410382
> R=vabr@chromium.org
>
> Committed: https://crrev.com/c3e50e6354188999da307094c5c037d5933f1bc3
> Cr-Commit-Position: refs/heads/master@{#308787}

TBR=jochen@chromium.org,jam@chromium.org,vabr@chromium.org,mkwst@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=410382

Review URL: https://codereview.chromium.org/809103003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#308834}

Fireblend/chromium-crosswalk,jaruba/chromium.src,Pluto-tv/chromium-crosswalk,M4sse/chromium.src,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,markYoungH/chromium.src,Fireblend/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,hgl888/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,Chilledheart/chromium,chuan9/chromium-crosswalk,fujunwei/chromium-crosswalk,dednal/chromium.src,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,M4sse/chromium.src,PeterWangIntel/chromium-crosswalk,Jonekee/chromium.src,Jonekee/chromium.src,dushu1203/chromium.src,chuan9/chromium-crosswalk,krieger-od/nwjs_chromium.src,M4sse/chromium.src,ltilve/chromium,M4sse/chromium.src,hgl888/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,jaruba/chromium.src,Jonekee/chromium.src,hgl888/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,dushu1203/chromium.src,krieger-od/nwjs_chromium.src,Fireblend/chromium-crosswalk,chuan9/chromium-crosswalk,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,fujunwei/chromium-crosswalk,Just-D/chromium-1,Just-D/chromium-1,Just-D/chromium-1,fujunwei/chromium-crosswalk,axinging/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,chuan9/chromium-crosswalk,ltilve/chromium,Pluto-tv/chromium-crosswalk,Chilledheart/chromium,fujunwei/chromium-crosswalk,dushu1203/chromium.src,M4sse/chromium.src,axinging/chromium-crosswalk,dushu1203/chromium.src,Jonekee/chromium.src,axinging/chromium-crosswalk,M4sse/chromium.src,markYoungH/chromium.src,TheTypoMaster/chromium-crosswalk,Jonekee/chromium.src,axinging/chromium-crosswalk,axinging/chromium-crosswalk,dednal/chromium.src,ltilve/chromium,Jonekee/chromium.src,fujunwei/chromium-crosswalk,Jonekee/chromium.src,dednal/chromium.src,dednal/chromium.src,Fireblend/chromium-crosswalk,Chilledheart/chromium,krieger-od/nwjs_chromium.src,ltilve/chromium,Fireblend/chromium-crosswalk,M4sse/chromium.src,dushu1203/chromium.src,mohamed--abdel-maksoud/chromium.src,axinging/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,dushu1203/chromium.src,krieger-od/nwjs_chromium.src,axinging/chromium-crosswalk,Jonekee/chromium.src,jaruba/chromium.src,markYoungH/chromium.src,jaruba/chromium.src,Just-D/chromium-1,hgl888/chromium-crosswalk,markYoungH/chromium.src,dednal/chromium.src,jaruba/chromium.src,Fireblend/chromium-crosswalk,krieger-od/nwjs_chromium.src,Jonekee/chromium.src,markYoungH/chromium.src,Just-D/chromium-1,Pluto-tv/chromium-crosswalk,markYoungH/chromium.src,ltilve/chromium,Pluto-tv/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Jonekee/chromium.src,Just-D/chromium-1,dednal/chromium.src,hgl888/chromium-crosswalk,Fireblend/chromium-crosswalk,Just-D/chromium-1,Pluto-tv/chromium-crosswalk,krieger-od/nwjs_chromium.src,axinging/chromium-crosswalk,Pluto-tv/chromium-crosswalk,M4sse/chromium.src,fujunwei/chromium-crosswalk,dushu1203/chromium.src,Pluto-tv/chromium-crosswalk,ltilve/chromium,markYoungH/chromium.src,chuan9/chromium-crosswalk,hgl888/chromium-crosswalk,Chilledheart/chromium,chuan9/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,jaruba/chromium.src,dednal/chromium.src,jaruba/chromium.src,PeterWangIntel/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,TheTypoMaster/chromium-crosswalk,krieger-od/nwjs_chromium.src,dushu1203/chromium.src,chuan9/chromium-crosswalk,dednal/chromium.src,krieger-od/nwjs_chromium.src,dednal/chromium.src,Jonekee/chromium.src,PeterWangIntel/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Chilledheart/chromium,mohamed--abdel-maksoud/chromium.src,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,chuan9/chromium-crosswalk,krieger-od/nwjs_chromium.src,Chilledheart/chromium,PeterWangIntel/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,krieger-od/nwjs_chromium.src,TheTypoMaster/chromium-crosswalk,dushu1203/chromium.src,Just-D/chromium-1,hgl888/chromium-crosswalk,ltilve/chromium,Chilledheart/chromium,markYoungH/chromium.src,krieger-od/nwjs_chromium.src,Just-D/chromium-1,Chilledheart/chromium,Fireblend/chromium-crosswalk,jaruba/chromium.src,TheTypoMaster/chromium-crosswalk,ltilve/chromium,PeterWangIntel/chromium-crosswalk,M4sse/chromium.src,Chilledheart/chromium,mohamed--abdel-maksoud/chromium.src,chuan9/chromium-crosswalk,jaruba/chromium.src,fujunwei/chromium-crosswalk,ltilve/chromium,M4sse/chromium.src,dushu1203/chromium.src,axinging/chromium-crosswalk,dednal/chromium.src,axinging/chromium-crosswalk,fujunwei/chromium-crosswalk,hgl888/chromium-crosswalk,fujunwei/chromium-crosswalk,Pluto-tv/chromium-crosswalk,dushu1203/chromium.src,jaruba/chromium.src,jaruba/chromium.src,mohamed--abdel-maksoud/chromium.src,M4sse/chromium.src,hgl888/chromium-crosswalk,dednal/chromium.src