[Nearby] Fix small layout bugs in the Contact Tab.

Fix the dom-repeat element typo in the Contact Tab and fixed the
spacing between list elements, as seen here:
https://screenshot.googleplex.com/eb1d918c-0c7a-4890-8086-8ef893ef27f4.

Bug: 1093634
Change-Id: Ifc586dd982e28d3ee2853359cb8cfa8e220ceb0d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2368332Reviewed-by: Josh Nohle <nohle@chromium.org>
Commit-Queue: Juliet Levesque <julietlevesque@google.com>
Cr-Commit-Position: refs/heads/master@{#800440}

chrome/browser/resources/nearby_internals/contact_object.html

@@ -59,11 +59,9 @@
     </cr-expand-button>
   </div>
   <iron-collapse opened="[[contentExpanded_]]">
-    <p class="expanded-element-title">Contact Records:
-      <p class="expanded-element">[[item.contactRecords]]</p>
-    </p>
-    <p class="expanded-element-title">Allowed Contact Ids:
-      <p class="expanded-element">[[item.allowedIds]]</p>
-    </p>
+    <p class="expanded-element-title">Contact Records:</p>
+    <p class="expanded-element">[[item.contactRecords]]</p>
+    <p class="expanded-element-title">Allowed Contact Ids:</p>
+    <p class="expanded-element">[[item.allowedIds]]</p>
   </iron-collapse>
 </div>

chrome/browser/resources/nearby_internals/contact_tab.html

@@ -18,7 +18,7 @@
     id="clearButton" disabled="[[!contactList_.length]]">
  Clear Messages
 </cr-button>
-<doom-repeat items="[[contactList_]]" as="contact" id="contact-list"
+<dom-repeat items="[[contactList_]]" as="contact" id="contact-list"
     hidden="[[!contactList_.length]]">
   <template>
     <contact-object item="[[contact]]">