Clean up GetMinOrMaxAppLaunchOrdinalsOnPage
Clean up GetMinOrMaxAppLaunchOrdinalsOnPage

Clean up GetMinOrMaxAppLaunchOrdinalsOnPage to use the  generated map to quickly find the the min or max app launch ordinal on a page, instead of checking all of the apps.

BUG=110762
TEST=unit_tests:ExtensionSorting*


Review URL: http://codereview.chromium.org/9289055

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@119524 0039d316-1c4b-4281-b951-d872f2087c98

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