Clicking the magnifying glass should perform search

In forum search is only working when user enter some
text in the search textfield and press the Enter
button. It should also work when we click on
magnifying glass.

TNL-526

common/static/coffee/spec/discussion/view/discussion_thread_list_view_spec.coffee

@@ -16,6 +16,7 @@ describe "DiscussionThreadListView", ->
                     <label>
                         <span class="sr">Search</span>
                         <input class="forum-nav-search-input" type="text" placeholder="Search all posts">
+                        <i class="icon icon-search"></i>
                     </label>
                 </form>
             </div>
@@ -331,6 +332,20 @@ describe "DiscussionThreadListView", ->
             @view.collection.trigger("change", new Thread({id: 1}))
             expect(@view.clearSearchAlerts).toHaveBeenCalled()
 
+    describe "Search events", ->
+
+      it "perform search when enter pressed inside search textfield", ->
+        setupAjax()
+        spyOn(@view, "searchFor")
+        @view.$el.find(".forum-nav-search-input").trigger($.Event("keydown", {which: 13}))
+        expect(@view.searchFor).toHaveBeenCalled()
+
+      it "perform search when search icon is clicked", ->
+        setupAjax()
+        spyOn(@view, "searchFor")
+        @view.$el.find(".icon-search").click()
+        expect(@view.searchFor).toHaveBeenCalled()
+
     describe "username search", ->
 
         it "makes correct ajax calls", ->

common/static/coffee/src/discussion/views/discussion_thread_list_view.coffee

@@ -7,6 +7,7 @@ if Backbone?
       "click .forum-nav-browse-menu-wrapper": "ignoreClick"
       "click .forum-nav-browse-title": "selectTopicHandler"
       "keydown .forum-nav-search-input": "performSearch"
+      "click .icon-search": "performSearch"
       "change .forum-nav-sort-control": "sortThreads"
       "click .forum-nav-thread-link": "threadSelected"
       "click .forum-nav-load-more-link": "loadMorePages"
@@ -425,7 +426,8 @@ if Backbone?
       @retrieveFirstPage(event)
 
     performSearch: (event) ->
-      if event.which == 13
+      #event.which 13 represent the Enter button 
+      if event.which == 13 or event.type == 'click'
         event.preventDefault()
         @hideBrowseMenu()
         @setCurrentTopicDisplay(gettext("Search Results"))