Flush more often in gclient's SubprocessCallAndFilter.
Flush more often in gclient's SubprocessCallAndFilter.

Speed up flushing of output on platforms that may not
flush as often as we expect (like Windows).  Wait at
least 10s between flushes to avoid overloading busy
readers.

BUG=none
TEST=gclient flushes on Windows more often, regular
gclient operations continue to work as expected
Review URL: http://codereview.chromium.org/3140013

git-svn-id: fd409f4bdeea2bb50a5d34bb4d4bfc2046a5a3dd@56217 0039d316-1c4b-4281-b951-d872f2087c98

Midrya/chromium,yetu/repotools,gcodetogit/depot_tools,fracting/depot_tools,Neozaru/depot_tools,G-P-S/depot_tools,liaorubei/depot_tools,jankeromnes/depot_tools,aleonliao/depot_tools,SuYiling/chrome_depot_tools,cpanelli/-git-clone-https-chromium.googlesource.com-chromium-tools-depot_tools,primiano/depot_tools,HackFisher/depot_tools,sarvex/depot-tools,azunite/chrome_build,eatbyte/depot_tools,SuYiling/chrome_depot_tools,coreos/depot_tools,liaorubei/depot_tools,G-P-S/depot_tools,mlufei/depot_tools,disigma/depot_tools,Midrya/chromium,withtone/depot_tools,jankeromnes/depot_tools,npe9/depot_tools,eatbyte/depot_tools,smikes/depot_tools,Neozaru/depot_tools,airtimemedia/depot_tools,airtimemedia/depot_tools,cybertk/depot_tools,gcodetogit/depot_tools,G-P-S/depot_tools,ajohnson23/depot_tools,ajohnson23/depot_tools,Neozaru/depot_tools,primiano/depot_tools,withtone/depot_tools,cybertk/depot_tools,kromain/chromium-tools,fanjunwei/depot_tools,smikes/depot_tools,cybertk/depot_tools,Phonebooth/depot_tools,eatbyte/depot_tools,yetu/repotools,duanwujie/depot_tools,hsharsha/depot_tools,aleonliao/depot_tools,Phonebooth/depot_tools,fracting/depot_tools,Midrya/chromium,chinmaygarde/depot_tools,fanjunwei/depot_tools,primiano/depot_tools,smikes/depot_tools,azunite/chrome_build,kaiix/depot_tools,michalliu/chromium-depot_tools,gcodetogit/depot_tools,cpanelli/-git-clone-https-chromium.googlesource.com-chromium-tools-depot_tools,cybertk/depot_tools,CoherentLabs/depot_tools,HackFisher/depot_tools,mlufei/depot_tools,CoherentLabs/depot_tools,jankeromnes/depot_tools,fracting/depot_tools,xuyuhan/depot_tools,michalliu/chromium-depot_tools,cybertk/depot_tools,jankeromnes/depot_tools,duanwujie/depot_tools,aleonliao/depot_tools,jankeromnes/depot_tools,jankeromnes/depot_tools,chinmaygarde/depot_tools,airtimemedia/depot_tools,HackFisher/depot_tools,disigma/depot_tools,liaorubei/depot_tools,coreos/depot_tools,Phonebooth/depot_tools,michalliu/chromium-depot_tools,duongbaoduy/gtools,sarvex/depot-tools,kromain/chromium-tools,Neozaru/depot_tools,SuYiling/chrome_depot_tools,yetu/repotools,smikes/depot_tools,Chilledheart/depot_tools,withtone/depot_tools,duongbaoduy/gtools,mlufei/depot_tools,Neozaru/depot_tools,ajohnson23/depot_tools,azureplus/chromium_depot_tools,fanjunwei/depot_tools,hsharsha/depot_tools,kromain/chromium-tools,kaiix/depot_tools,airtimemedia/depot_tools,Chilledheart/depot_tools,chinmaygarde/depot_tools,Chilledheart/depot_tools,fanjunwei/depot_tools,eatbyte/depot_tools,G-P-S/depot_tools,disigma/depot_tools,smikes/depot_tools,sarvex/depot-tools,hsharsha/depot_tools,coreos/depot_tools,xuyuhan/depot_tools,kaiix/depot_tools,azunite/chrome_build,npe9/depot_tools,cpanelli/-git-clone-https-chromium.googlesource.com-chromium-tools-depot_tools,xuyuhan/depot_tools,Chilledheart/depot_tools,kromain/chromium-tools,npe9/depot_tools,npe9/depot_tools,xuyuhan/depot_tools,coreos/depot_tools,coreos/depot_tools,azureplus/chromium_depot_tools,HackFisher/depot_tools,coreos/depot_tools,Phonebooth/depot_tools,Chilledheart/depot_tools,duanwujie/depot_tools,michalliu/chromium-depot_tools,jankeromnes/depot_tools,duongbaoduy/gtools,liaorubei/depot_tools,sarvex/depot-tools,azureplus/chromium_depot_tools