Search bar should always clear internal text state

This fixes a situation where the search bar would not be able to clear
when the last search performed was empty.

h/static/scripts/directives/simple-search.coffee

@@ -6,6 +6,7 @@ simpleSearch = ['$parse', ($parse) ->
     scope.reset = (event) ->
       event.preventDefault()
       scope.query = ''
+      scope.searchtext = ''
 
     scope.search = (event) ->
       event.preventDefault()

tests/js/directives/simple-search-test.coffee

@@ -46,6 +46,8 @@ describe 'h.directives', ->
       assert($scope.clear.called)
 
     it 'clears the search-bar', ->
+      isolate.query = ''
+      isolate.$digest()
       isolate.searchtext = "Test query"
       isolate.$digest()
       $element.find('.simple-search-clear').click()