MD History: Add spinners when new data is loading or searching

chrome/browser/resources/md_history/history.js

Index: chrome/browser/resources/md_history/history.js
diff --git a/chrome/browser/resources/md_history/history.js b/chrome/browser/resources/md_history/history.js
index 72aecafbc29c9dae800ea9c19dee33d8b8b571fc..4d2cfe3a8689e9c778790905be3e55c7df905198 100644
--- a/chrome/browser/resources/md_history/history.js
+++ b/chrome/browser/resources/md_history/history.js
@@ -66,6 +66,7 @@ window.addEventListener('delete-selected', function() {
 window.addEventListener('search-changed', function(e) {
   $('toolbar').setSearchTerm(e.detail.search);
   /** @type {HistoryListElement} */($('history-list')).setLoading();
+  /** @type {HistoryToolbarElement} */($('toolbar')).searching_ = true;
   chrome.send('queryHistory', [e.detail.search, 0, 0, 0, RESULTS_PER_PAGE]);
 });
 
@@ -90,6 +91,7 @@ function historyResult(info, results) {
   waitForUpgrade(listElem).then(function() {
     var list = /** @type {HistoryListElement} */(listElem);
     list.addNewResults(results, info.term);
+    $('toolbar').searching_ = false;

[tsergeant, 2016/04/18 01:26:36]

Nit: Add the /** @type {HistoryToolbarElement} */ annotation, like above on line
69.

You can run the closure compiler which uses these annotations with:
  third_party/closure_compiler/run_compiler

(there are full docs here:
https://chromium.googlesource.com/chromium/src/+/master/docs/closure_compilat...)

[lshang, 2016/04/22 01:25:03]

Done.

     if (info.finished)
       list.disableResultLoading();
     // TODO(tsergeant): Showing everything as soon as the list is ready is not