Limit supported console methods

Replaced all console.log with console.info, limit supported
console methods.

`console.info`, `warn`, `error`, `assert` are more meaningful
than generic `log`. This will also help prevent having log prints
left by accident.

Updated rule:

`"no-console": ["error",
  { allow: ["warn", "error", "info", "assert", "group", "groupEnd"] }
]`

Change-Id: I88e8b1b0aea8659a206ddae642023efc1572f5f1

polygerrit-ui/app/elements/core/gr-router/gr-router.js

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 792a751..60722d3 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router.js
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router.js
@@ -201,7 +201,7 @@
 // gr-router and gr-app in the PolyGerritIndexHtml.soy file if needed
 const app = document.querySelector('#app');
 if (!app) {
-  console.log('No gr-app found (running tests)');
+  console.info('No gr-app found (running tests)');
 }
 
 // Setup listeners outside of the router component initialization.