MD History: Add shortcuts for 'Delete' and 'Backspace' to delete selected items

Press 'Delete' or 'Backspace' key from keyboard will delete selected history items
on MD History.

BUG=627408
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2159773003
Cr-Commit-Position: refs/heads/master@{#406715}

chrome/browser/resources/md_history/app.js

@@ -159,6 +159,9 @@ Polymer({
             !(this.$.toolbar.searchBar.showingSearch &&
               this.$.toolbar.searchBar.isSearchFocused());
         break;
+      case 'delete-command':
+        e.canExecute = this.$.toolbar.count > 0;
+        break;
     }
   },
 
@@ -186,6 +189,8 @@ Polymer({
   onCommand_: function(e) {
     if (e.command.id == 'find-command' || e.command.id == 'slash-command')
       this.$.toolbar.showSearchField();
+    if (e.command.id == 'delete-command')
+      this.deleteSelected();
   },
 
   /**

chrome/browser/resources/md_history/history.html

@@ -75,6 +75,7 @@
 <if expr="not is_macosx">
   <command id="find-command" shortcut="Ctrl|f">
 </if>
+  <command id="delete-command" shortcut="Delete Backspace">
   <command id="slash-command" shortcut="/">
 
   <link rel="import" href="chrome://resources/html/cr.html">

chrome/test/data/webui/md_history/history_list_test.js

@@ -231,6 +231,45 @@ cr.define('md_history.history_list_test', function() {
         });
       });
 
+      test('deleting items using shortcuts', function(done) {
+        var listContainer = app.$.history;
+        app.historyResult(createHistoryInfo(), TEST_HISTORY_RESULTS);
+        flush().then(function() {
+          items = Polymer.dom(element.root).querySelectorAll('history-item');
+
+          // Dialog should not appear when there is no item selected.
+          MockInteractions.pressAndReleaseKeyOn(
+            document.body, 46, '', 'Delete');
+          assertFalse(listContainer.$.dialog.opened);
+
+          MockInteractions.tap(items[1].$.checkbox);
+          MockInteractions.tap(items[2].$.checkbox);
+
+          assertEquals(2, toolbar.count);
+
+          registerMessageCallback('removeVisits', this, function(toRemove) {
+            assertEquals('https://www.example.com', toRemove[0].url);
+            assertEquals('https://www.google.com', toRemove[1].url);
+            assertEquals('2016-03-14 10:00 UTC', toRemove[0].timestamps[0]);
+            assertEquals('2016-03-14 9:00 UTC', toRemove[1].timestamps[0]);
+            done();
+          });
+
+          MockInteractions.pressAndReleaseKeyOn(
+            document.body, 46, '', 'Delete');
+          assertTrue(listContainer.$.dialog.opened);
+
+          MockInteractions.tap(listContainer.$$('.cancel-button'));
+          assertFalse(listContainer.$.dialog.opened);
+
+          MockInteractions.pressAndReleaseKeyOn(
+            document.body, 8, '', 'Backspace');
+          assertTrue(listContainer.$.dialog.opened);
+
+          MockInteractions.tap(listContainer.$$('.action-button'));
+        });
+      });
+
       teardown(function() {
         element.historyData_ = [];
         registerMessageCallback('removeVisits', this, undefined);