UX: Add "solved" status filter in advanced search page.

And rename `in:solved` to `status:solved`.

assets/javascripts/discourse/initializers/extend-for-solved-button.js.es6

@@ -9,6 +9,7 @@ import PostCooked from "discourse/widgets/post-cooked";
 import { formatUsername } from "discourse/lib/utilities";
 import { iconHTML } from "discourse-common/lib/icon-library";
 import { iconNode } from "discourse-common/lib/icon-library";
+import SearchAdvancedOptions from "discourse/components/search-advanced-options";
 
 function clearAccepted(topic) {
   const posts = topic.get("postStream.posts");
@@ -262,6 +263,16 @@ export default {
       })
     });
 
+    SearchAdvancedOptions.reopen({
+      didInsertElement() {
+        this._super();
+        this.statusOptions.push({
+          name: I18n.t("search.advanced.statuses.solved"),
+          value: "solved"
+        });
+      }
+    });
+
     withPluginApi("0.1", initializeWithApi);
 
     withPluginApi("0.8.10", api => {

config/locales/client.en.yml

@@ -27,3 +27,8 @@ en:
     topic_statuses:
       solved:
         help: "This topic has a solution"
+
+    search:
+      advanced:
+        statuses:
+          solved: "are solved"

plugin.rb

@@ -465,7 +465,7 @@ SQL
 
   #TODO Remove when plugin is 1.0
   if Search.respond_to? :advanced_filter
-    Search.advanced_filter(/in:solved/) do |posts|
+    Search.advanced_filter(/status:solved/) do |posts|
       posts.where("topics.id IN (
         SELECT tc.topic_id
         FROM topic_custom_fields tc
@@ -475,7 +475,7 @@ SQL
 
     end
 
-    Search.advanced_filter(/in:unsolved/) do |posts|
+    Search.advanced_filter(/status:unsolved/) do |posts|
       posts.where("topics.id NOT IN (
         SELECT tc.topic_id
         FROM topic_custom_fields tc