Implement the private API for quick unlock.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index eeea9193acb9d4e9a4283bcdc7b6759c2d6d35be..45ec5e44dcd37b59c9c2db731eb0a7d3432c11c9 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -72246,6 +72246,10 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="1133" label="SYSTEM_DISPLAY_OVERSCANCALIBRATIONADJUST"/>
   <int value="1134" label="SYSTEM_DISPLAY_OVERSCANCALIBRATIONRESET"/>
   <int value="1135" label="SYSTEM_DISPLAY_OVERSCANCALIBRATIONCOMPLETE"/>
+  <int value="1136" label="QUICKUNLOCKPRIVATE_CHECKPASSWORD"/>

[Devlin, 2016/06/13 14:50:23]

?

[jdufault, 2016/06/20 22:18:25]

Done.

+  <int value="1137" label="QUICKUNLOCKPRIVATE_SETMODES"/>
+  <int value="1138" label="QUICKUNLOCKPRIVATE_GETACTIVEMODES"/>
+  <int value="1139" label="QUICKUNLOCKPRIVATE_GETAVAILABLEMODES"/>
 </enum>
 
 <enum name="ExtensionIconState" type="int">
@@ -72667,6 +72671,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="196" label="kEnterpriseDeviceAttributes"/>
   <int value="197" label="kCertificateProvider"/>
   <int value="198" label="kResourcesPrivate"/>
+  <int value="199" label="kQuickUnlockPrivate"/>
 </enum>
 
 <enum name="ExtensionServiceVerifyAllSuccess" type="int">