ListAvailablePlugins: Let RestApiServlet do the conversion to JSON

Also inline the display() method which had only a single caller.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I63a9275fe48ce68d8cf81ad82d4fe6a37aa96781

src/main/java/com/googlesource/gerrit/plugins/manager/ListAvailablePlugins.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/manager/ListAvailablePlugins.java b/src/main/java/com/googlesource/gerrit/plugins/manager/ListAvailablePlugins.java
index 96fb53f..d43bbec 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/manager/ListAvailablePlugins.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/manager/ListAvailablePlugins.java
@@ -20,9 +20,6 @@
 import com.google.gerrit.extensions.restapi.RestApiException;
 import com.google.gerrit.extensions.restapi.RestReadView;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
-import com.google.gerrit.json.OutputFormat;
-import com.google.gson.JsonElement;
-import com.google.gson.reflect.TypeToken;
 import com.google.inject.Inject;
 import com.googlesource.gerrit.plugins.manager.repository.PluginInfo;
 import java.util.ArrayList;
@@ -43,11 +40,7 @@
   }
 
   @Override
-  public Object apply(TopLevelResource resource) throws RestApiException {
-    return display();
-  }
-
-  public JsonElement display() throws RestApiException {
+  public Map<String, PluginInfo> apply(TopLevelResource resource) throws RestApiException {
     Map<String, PluginInfo> output = Maps.newTreeMap();
     List<PluginInfo> plugins;
     try {
@@ -68,8 +61,6 @@
       output.put(p.name, p);
     }
 
-    return OutputFormat.JSON
-        .newGson()
-        .toJsonTree(output, new TypeToken<Map<String, Object>>() {}.getType());
+    return output;
   }
 }