switch to beforemount hook & improve test timing logic

src/index.js

@@ -20,7 +20,7 @@ export default function VueMeta (Vue) {
 
   // watch for client side component updates
   Vue.mixin({
-    mounted () {
+    beforeMount () {
       // batch potential DOM updates to prevent extraneous re-rendering
       window.cancelAnimationFrame(requestId)
 
@@ -28,7 +28,7 @@ export default function VueMeta (Vue) {
         requestId = null
 
         // update the meta info
-        updateClientMetaInfo(getMetaInfo(this.$root))
+        updateClientMetaInfo(getMetaInfo(this.$root), this.$root)
       })
     }
   })

src/updateClientMetaInfo.js

@@ -11,7 +11,7 @@ if (typeof window !== 'undefined' && window !== null) {
  *
  * @param  {Object} newInfo - the meta info to update to
  */
-export default function updateClientMetaInfo (newInfo) {
+export default function updateClientMetaInfo (newInfo, $root) {
   // if this is not a server render, then update
   if (htmlTag.getAttribute(SERVER_RENDERED_ATTRIBUTE) === null) {
     if (newInfo.title) {
@@ -24,4 +24,9 @@ export default function updateClientMetaInfo (newInfo) {
   } else {
     htmlTag.removeAttribute(SERVER_RENDERED_ATTRIBUTE)
   }
+
+  // HACK: since we're performing DOM side effects, we can't rely on
+  // Vue.nextTick in our tests. This event helps keep the test suite
+  // free of setTimeout clutter
+  $root.$emit('vue-meta-update')
 }