Added uma for pin unlock set up.

chrome/browser/resources/settings/people_page/lock_screen.js

Index: chrome/browser/resources/settings/people_page/lock_screen.js
diff --git a/chrome/browser/resources/settings/people_page/lock_screen.js b/chrome/browser/resources/settings/people_page/lock_screen.js
index f296363be34d22c6969668a110d742ddcf0a9617..c929f2730b00ca8d2b928c05ab70548aa7d0e87d 100644
--- a/chrome/browser/resources/settings/people_page/lock_screen.js
+++ b/chrome/browser/resources/settings/people_page/lock_screen.js
@@ -37,6 +37,18 @@ Polymer({
       type: Object,
       observer: 'onSetModesChanged_'
     },
+
+    /**
+     * writeUma_ is a function that handles writing uma stats. It may be
+     * overridden for tests.
+     *
+     * @type {Function}
+     * @private
+     */
+    writeUma_: {
+      type: Object,
+      value: function() { return recordLockScreenProgress; }
+    }
   },
 
   /** selectedUnlockType is defined in LockStateBehavior. */
@@ -121,5 +133,6 @@ Polymer({
   /** @private */
   onConfigurePin_: function() {
     this.$.setupPin.open();
+    this.writeUma_(LockScreenProgress.CHOOSE_PIN_OR_PASSWORD);
   },
 });