Drop struct BootStat and all usage (boot stats are now sent from chromeos code).

BUG=141757


As far as I see, after migrating 

BootTime.Total                                                                   
BootTime.Firmware                                                                
BootTime.Kernel                                                                  
BootTime.System                                                                  
BootTime.Chrome

to chromeos, struct chromeos::BootTimesLoader::BootTimes becomes empty. So I've dropped it completely and all references to it.


Probably class BootTimesLoader  should also be renamed as it doesn't load any times anymore, but instead reports time marks.


Please review.

Review URL: https://chromiumcodereview.appspot.com/22262004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@217006 0039d316-1c4b-4281-b951-d872f2087c98
7 files changed