[CrOS Tether] ProximityAuth WebUI improvement: show the local device's ID.

components/proximity_auth/webui/resources/proximity_auth.js

Index: components/proximity_auth/webui/resources/proximity_auth.js
diff --git a/components/proximity_auth/webui/resources/proximity_auth.js b/components/proximity_auth/webui/resources/proximity_auth.js
index c9d1928f7af9410bb9fae2ef98b226129d23f023..764c6ae06f21aa38a42e783055b110ef0f88bdf0 100644
--- a/components/proximity_auth/webui/resources/proximity_auth.js
+++ b/components/proximity_auth/webui/resources/proximity_auth.js
@@ -26,7 +26,7 @@ ProximityAuth = {
 class CryptAuthController {
   constructor() {
     this.elements_ = {
-      publicKey: document.getElementById('public-key'),
+      localDeviceId: document.getElementById('local-device-id'),
       gcmRegistration: document.getElementById('gcm-registration'),
       currentEid: document.getElementById('current-eid'),
       enrollmentTitle: document.getElementById('enrollment-title'),
@@ -43,6 +43,14 @@ class CryptAuthController {
     this.elements_.deviceSyncButton.onclick = this.forceDeviceSync_.bind(this);
   }
 
+  /**
+   * Sets the local device's ID. Note that this value is truncated since the
+   * full value is very long and does not cleanly fit on the screen.
+   */
+  setLocalDeviceId(deviceIdTruncated) {
+    this.elements_.localDeviceId.textContent = deviceIdTruncated;
+  }
+
   /**
    * Update the enrollment state in the UI.
    */
@@ -253,12 +261,18 @@ class EligibleDevicesController {
  * Interface for the native WebUI to call into our JS.
  */
 LocalStateInterface = {
-  onGotLocalState: function(enrollmentState, deviceSyncState, remoteDevices) {
+  onGotLocalState: function(
+      localDeviceId, enrollmentState, deviceSyncState, remoteDevices) {
+    LocalStateInterface.setLocalDeviceId(localDeviceId);
     LocalStateInterface.onEnrollmentStateChanged(enrollmentState);
     LocalStateInterface.onDeviceSyncStateChanged(deviceSyncState);
     LocalStateInterface.onRemoteDevicesChanged(remoteDevices);
   },
 
+  setLocalDeviceId: function(localDeviceId) {
+    ProximityAuth.cryptauthController_.setLocalDeviceId(localDeviceId);
+  },
+
   onEnrollmentStateChanged: function(enrollmentState) {
     ProximityAuth.cryptauthController_.updateEnrollmentState(enrollmentState);
   },