Fix minor error it SDCH filter code (hidden by filter control code)
Fix minor error it SDCH filter code (hidden by filter control code)

The controlling code in filter.cc doesn't significantly distinguish
FILTER_OK and FILTER_NEEDS_MORE_DATA, but we *should* transition
to a semantic where FILTER_OK becomes instead "FILTER_NEEDS_OUTPUT_SPACE"
and then we'd need to do this uniformly for all filter code.
We *could* then improve the driving filter code (for example, not have
to sniff output buffer usage to deduce that the filter wanted to be 
called again to emit more data).

r=huanr
Review URL: http://codereview.chromium.org/28193

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@10544 0039d316-1c4b-4281-b951-d872f2087c98

markYoungH/chromium.src,junmin-zhu/chromium-rivertrail,Just-D/chromium-1,dushu1203/chromium.src,chuan9/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,keishi/chromium,PeterWangIntel/chromium-crosswalk,keishi/chromium,zcbenz/cefode-chromium,junmin-zhu/chromium-rivertrail,Chilledheart/chromium,hgl888/chromium-crosswalk-efl,mohamed--abdel-maksoud/chromium.src,hgl888/chromium-crosswalk,hgl888/chromium-crosswalk-efl,axinging/chromium-crosswalk,jaruba/chromium.src,axinging/chromium-crosswalk,mogoweb/chromium-crosswalk,Just-D/chromium-1,dednal/chromium.src,ondra-novak/chromium.src,mohamed--abdel-maksoud/chromium.src,pozdnyakov/chromium-crosswalk,dushu1203/chromium.src,mohamed--abdel-maksoud/chromium.src,TheTypoMaster/chromium-crosswalk,hujiajie/pa-chromium,Jonekee/chromium.src,bright-sparks/chromium-spacewalk,chuan9/chromium-crosswalk,Fireblend/chromium-crosswalk,fujunwei/chromium-crosswalk,hgl888/chromium-crosswalk-efl,timopulkkinen/BubbleFish,hujiajie/pa-chromium,jaruba/chromium.src,Pluto-tv/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Chilledheart/chromium,Jonekee/chromium.src,hujiajie/pa-chromium,nacl-webkit/chrome_deps,patrickm/chromium.src,hgl888/chromium-crosswalk,zcbenz/cefode-chromium,dednal/chromium.src,mogoweb/chromium-crosswalk,fujunwei/chromium-crosswalk,keishi/chromium,M4sse/chromium.src,junmin-zhu/chromium-rivertrail,PeterWangIntel/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,hujiajie/pa-chromium,ChromiumWebApps/chromium,jaruba/chromium.src,junmin-zhu/chromium-rivertrail,littlstar/chromium.src,anirudhSK/chromium,ChromiumWebApps/chromium,nacl-webkit/chrome_deps,hujiajie/pa-chromium,Pluto-tv/chromium-crosswalk,dednal/chromium.src,rogerwang/chromium,rogerwang/chromium,Just-D/chromium-1,mohamed--abdel-maksoud/chromium.src,markYoungH/chromium.src,krieger-od/nwjs_chromium.src,PeterWangIntel/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,dednal/chromium.src,nacl-webkit/chrome_deps,M4sse/chromium.src,robclark/chromium,PeterWangIntel/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,timopulkkinen/BubbleFish,timopulkkinen/BubbleFish,Jonekee/chromium.src,hujiajie/pa-chromium,M4sse/chromium.src,TheTypoMaster/chromium-crosswalk,markYoungH/chromium.src,fujunwei/chromium-crosswalk,Just-D/chromium-1,dushu1203/chromium.src,PeterWangIntel/chromium-crosswalk,Jonekee/chromium.src,Jonekee/chromium.src,jaruba/chromium.src,dushu1203/chromium.src,pozdnyakov/chromium-crosswalk,markYoungH/chromium.src,littlstar/chromium.src,krieger-od/nwjs_chromium.src,hgl888/chromium-crosswalk-efl,zcbenz/cefode-chromium,pozdnyakov/chromium-crosswalk,hgl888/chromium-crosswalk,hujiajie/pa-chromium,chuan9/chromium-crosswalk,M4sse/chromium.src,axinging/chromium-crosswalk,robclark/chromium,M4sse/chromium.src,markYoungH/chromium.src,junmin-zhu/chromium-rivertrail,hujiajie/pa-chromium,Chilledheart/chromium,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,nacl-webkit/chrome_deps,robclark/chromium,pozdnyakov/chromium-crosswalk,Fireblend/chromium-crosswalk,zcbenz/cefode-chromium,fujunwei/chromium-crosswalk,markYoungH/chromium.src,timopulkkinen/BubbleFish,krieger-od/nwjs_chromium.src,crosswalk-project/chromium-crosswalk-efl,M4sse/chromium.src,timopulkkinen/BubbleFish,Pluto-tv/chromium-crosswalk,Fireblend/chromium-crosswalk,ChromiumWebApps/chromium,Jonekee/chromium.src,timopulkkinen/BubbleFish,M4sse/chromium.src,mogoweb/chromium-crosswalk,robclark/chromium,axinging/chromium-crosswalk,ltilve/chromium,keishi/chromium,axinging/chromium-crosswalk,pozdnyakov/chromium-crosswalk,Chilledheart/chromium,dednal/chromium.src,patrickm/chromium.src,keishi/chromium,dednal/chromium.src,zcbenz/cefode-chromium,rogerwang/chromium,chuan9/chromium-crosswalk,littlstar/chromium.src,robclark/chromium,crosswalk-project/chromium-crosswalk-efl,dednal/chromium.src,hgl888/chromium-crosswalk-efl,markYoungH/chromium.src,crosswalk-project/chromium-crosswalk-efl,jaruba/chromium.src,timopulkkinen/BubbleFish,zcbenz/cefode-chromium,mogoweb/chromium-crosswalk,timopulkkinen/BubbleFish,littlstar/chromium.src,krieger-od/nwjs_chromium.src,TheTypoMaster/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,bright-sparks/chromium-spacewalk,ltilve/chromium,hujiajie/pa-chromium,patrickm/chromium.src,timopulkkinen/BubbleFish,hujiajie/pa-chromium,TheTypoMaster/chromium-crosswalk,ChromiumWebApps/chromium,ltilve/chromium,pozdnyakov/chromium-crosswalk,patrickm/chromium.src,Fireblend/chromium-crosswalk,zcbenz/cefode-chromium,axinging/chromium-crosswalk,rogerwang/chromium,mogoweb/chromium-crosswalk,ltilve/chromium,nacl-webkit/chrome_deps,anirudhSK/chromium,Jonekee/chromium.src,ondra-novak/chromium.src,dednal/chromium.src,hgl888/chromium-crosswalk-efl,dushu1203/chromium.src,rogerwang/chromium,mohamed--abdel-maksoud/chromium.src,ondra-novak/chromium.src,keishi/chromium,Jonekee/chromium.src,patrickm/chromium.src,junmin-zhu/chromium-rivertrail,zcbenz/cefode-chromium,junmin-zhu/chromium-rivertrail,anirudhSK/chromium,ChromiumWebApps/chromium,nacl-webkit/chrome_deps,chuan9/chromium-crosswalk,crosswalk-project/chromium-crosswalk-efl,anirudhSK/chromium,pozdnyakov/chromium-crosswalk,krieger-od/nwjs_chromium.src,junmin-zhu/chromium-rivertrail,Just-D/chromium-1,rogerwang/chromium,Fireblend/chromium-crosswalk,keishi/chromium,axinging/chromium-crosswalk,ChromiumWebApps/chromium,krieger-od/nwjs_chromium.src,markYoungH/chromium.src,anirudhSK/chromium,crosswalk-project/chromium-crosswalk-efl,anirudhSK/chromium,jaruba/chromium.src,nacl-webkit/chrome_deps,zcbenz/cefode-chromium,bright-sparks/chromium-spacewalk,dushu1203/chromium.src,M4sse/chromium.src,anirudhSK/chromium,jaruba/chromium.src,dushu1203/chromium.src,hgl888/chromium-crosswalk,Chilledheart/chromium,Pluto-tv/chromium-crosswalk,hgl888/chromium-crosswalk,patrickm/chromium.src,jaruba/chromium.src,ondra-novak/chromium.src,Pluto-tv/chromium-crosswalk,rogerwang/chromium,robclark/chromium,hgl888/chromium-crosswalk-efl,ondra-novak/chromium.src,keishi/chromium,mogoweb/chromium-crosswalk,krieger-od/nwjs_chromium.src,patrickm/chromium.src,bright-sparks/chromium-spacewalk,anirudhSK/chromium,Pluto-tv/chromium-crosswalk,ltilve/chromium,fujunwei/chromium-crosswalk,ChromiumWebApps/chromium,ChromiumWebApps/chromium,littlstar/chromium.src,chuan9/chromium-crosswalk,anirudhSK/chromium,ltilve/chromium,Chilledheart/chromium,pozdnyakov/chromium-crosswalk,krieger-od/nwjs_chromium.src,markYoungH/chromium.src,dednal/chromium.src,ondra-novak/chromium.src,dushu1203/chromium.src,Just-D/chromium-1,markYoungH/chromium.src,ondra-novak/chromium.src,axinging/chromium-crosswalk,nacl-webkit/chrome_deps,Jonekee/chromium.src,krieger-od/nwjs_chromium.src,robclark/chromium,Chilledheart/chromium,bright-sparks/chromium-spacewalk,fujunwei/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,timopulkkinen/BubbleFish,junmin-zhu/chromium-rivertrail,fujunwei/chromium-crosswalk,jaruba/chromium.src,dednal/chromium.src,Just-D/chromium-1,ondra-novak/chromium.src,mohamed--abdel-maksoud/chromium.src,rogerwang/chromium,M4sse/chromium.src,axinging/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,hgl888/chromium-crosswalk,robclark/chromium,patrickm/chromium.src,Jonekee/chromium.src,Chilledheart/chromium,dushu1203/chromium.src,krieger-od/nwjs_chromium.src,ltilve/chromium,mogoweb/chromium-crosswalk,dushu1203/chromium.src,mohamed--abdel-maksoud/chromium.src,robclark/chromium,hgl888/chromium-crosswalk,crosswalk-project/chromium-crosswalk-efl,crosswalk-project/chromium-crosswalk-efl,patrickm/chromium.src,hgl888/chromium-crosswalk,bright-sparks/chromium-spacewalk,ChromiumWebApps/chromium,dushu1203/chromium.src,TheTypoMaster/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,chuan9/chromium-crosswalk,jaruba/chromium.src,ltilve/chromium,Fireblend/chromium-crosswalk,anirudhSK/chromium,Pluto-tv/chromium-crosswalk,pozdnyakov/chromium-crosswalk,Fireblend/chromium-crosswalk,nacl-webkit/chrome_deps,Just-D/chromium-1,ondra-novak/chromium.src,rogerwang/chromium,crosswalk-project/chromium-crosswalk-efl,chuan9/chromium-crosswalk,anirudhSK/chromium,chuan9/chromium-crosswalk,hgl888/chromium-crosswalk-efl,jaruba/chromium.src,littlstar/chromium.src,keishi/chromium,hgl888/chromium-crosswalk-efl,bright-sparks/chromium-spacewalk,ChromiumWebApps/chromium,ltilve/chromium,bright-sparks/chromium-spacewalk,junmin-zhu/chromium-rivertrail,Pluto-tv/chromium-crosswalk,dednal/chromium.src,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,anirudhSK/chromium,mogoweb/chromium-crosswalk,rogerwang/chromium,PeterWangIntel/chromium-crosswalk,M4sse/chromium.src,littlstar/chromium.src,fujunwei/chromium-crosswalk,hgl888/chromium-crosswalk-efl,pozdnyakov/chromium-crosswalk,hgl888/chromium-crosswalk,keishi/chromium,crosswalk-project/chromium-crosswalk-efl,nacl-webkit/chrome_deps,ChromiumWebApps/chromium,junmin-zhu/chromium-rivertrail,Just-D/chromium-1,markYoungH/chromium.src,bright-sparks/chromium-spacewalk,zcbenz/cefode-chromium,M4sse/chromium.src,Pluto-tv/chromium-crosswalk,zcbenz/cefode-chromium,ChromiumWebApps/chromium,Fireblend/chromium-crosswalk,krieger-od/nwjs_chromium.src,robclark/chromium,Fireblend/chromium-crosswalk,fujunwei/chromium-crosswalk,timopulkkinen/BubbleFish,keishi/chromium,hujiajie/pa-chromium,nacl-webkit/chrome_deps,mogoweb/chromium-crosswalk,mogoweb/chromium-crosswalk,littlstar/chromium.src,pozdnyakov/chromium-crosswalk,Jonekee/chromium.src,Chilledheart/chromium