PolyGerrit: Exclude plugins/* routes from catchall

Change-Id: Iaec88c7813e6bab747844e6c8689c7f163e6c97f
diff --git a/polygerrit-ui/app/elements/core/gr-router/gr-router.js b/polygerrit-ui/app/elements/core/gr-router/gr-router.js
index 1ce3c23..885a9ec 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router.js
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router.js
@@ -72,6 +72,8 @@
     TAG_LIST_FILTER_OFFSET:
         '/admin/projects/:project,tags/q/filter::filter,:offset',
 
+    PLUGINS: /^\/plugins\/(.+)$/,
+
     PLUGIN_LIST: /^\/admin\/plugins(\/)?$/,
 
     // Matches /admin/plugins[,<offset>][/].
@@ -474,6 +476,8 @@
 
       this._mapRoute(RoutePattern.PROJECT, '_handleProjectRoute');
 
+      this._mapRoute(RoutePattern.PLUGINS, '_handlePassThroughRoute');
+
       this._mapRoute(RoutePattern.PLUGIN_LIST_OFFSET,
           '_handlePluginListOffsetRoute', true);