Add user header to the dashboard view

Rework of the change reverted by 8380b02d6.

Change-Id: Ic50144ae7a0c1c075b1922e6b6387a38073da606
diff --git a/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js b/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js
index 750db92..0d56ac8 100644
--- a/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js
+++ b/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js
@@ -53,6 +53,8 @@
       },
       /** @type {{ selectedChangeIndex: number }} */
       viewState: Object,
+
+      /** @type {{ user: string }} */
       params: {
         type: Object,
       },
@@ -144,5 +146,8 @@
       return query.replace(/\$\{user\}/g, user);
     },
 
+    _computeUserHeaderClass(userParam) {
+      return userParam === 'self' ? 'hide' : '';
+    },
   });
 })();