Consolidate GPU blacklist histograms into fewer ones.
Consolidate GPU blacklist histograms into fewer ones.

Originally we have one for each feature, each OS platform (XP, Vista, Win7 as three).  Now we have one for each feature for all platforms, and one for each feature for Windows only (XP, Vista, and Win7 end up as different entries in one histogram). 

BUG=91876
TEST=tree green
Review URL: http://codereview.chromium.org/7860012

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@101451 0039d316-1c4b-4281-b951-d872f2087c98

gavinp/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,gavinp/chromium,adobe/chromium,ropik/chromium,yitian134/chromium,yitian134/chromium,ropik/chromium,gavinp/chromium,yitian134/chromium,ropik/chromium,ropik/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,gavinp/chromium,ropik/chromium,yitian134/chromium,yitian134/chromium,gavinp/chromium,adobe/chromium,ropik/chromium,gavinp/chromium,adobe/chromium,adobe/chromium,yitian134/chromium,adobe/chromium,gavinp/chromium,adobe/chromium,adobe/chromium,adobe/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,ropik/chromium,ropik/chromium,yitian134/chromium,ropik/chromium