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 09c97a711d5210200407b261225e316c629536f3..a8d8e5adedb8aef6893672dc41800218714875f7 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -71245,6 +71245,10 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="1128"
       label="BLUETOOTHLOWENERGY_NOTIFYCHARACTERISTICVALUECHANGED"/>
   <int value="1129" label="BLUETOOTHLOWENERGY_REMOVESERVICE"/>
+  <int value="1130" label="QUICKUNLOCKPRIVATE_CHECKPASSWORD"/>
+  <int value="1131" label="QUICKUNLOCKPRIVATE_SETMODES"/>
+  <int value="1132" label="QUICKUNLOCKPRIVATE_GETACTIVEMODES"/>
+  <int value="1133" label="QUICKUNLOCKPRIVATE_GETAVAILABLEMODES"/>
 </enum>
 
 <enum name="ExtensionInstallCause" type="int">
@@ -71660,6 +71664,7 @@ 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">