ListTags: Include timestamp in tag info

The tags are listed in alphanumeric order, but some clients may wish
to order the tags by the date they were created.

Add a timestamp in the tag info.

For annotated/signed tags, the timestamp is the date at which the tag
was created.

For lightweight tags, the timestamp is set to the committer timestamp,
only when the tag is on a commit.

Change-Id: I34f49f19810fa430769a50b5ae43b8107527792b

java/com/google/gerrit/extensions/api/projects/TagInfo.java

@@ -16,19 +16,47 @@ package com.google.gerrit.extensions.api.projects;
 
 import com.google.gerrit.extensions.common.GitPerson;
 import com.google.gerrit.extensions.common.WebLinkInfo;
+import java.sql.Timestamp;
 import java.util.List;
 
 public class TagInfo extends RefInfo {
   public String object;
   public String message;
   public GitPerson tagger;
+  public Timestamp created;
   public List<WebLinkInfo> webLinks;
 
-  public TagInfo(String ref, String revision, Boolean canDelete, List<WebLinkInfo> webLinks) {
+  public TagInfo(
+      String ref,
+      String revision,
+      Boolean canDelete,
+      List<WebLinkInfo> webLinks,
+      Timestamp created) {
     this.ref = ref;
     this.revision = revision;
     this.canDelete = canDelete;
     this.webLinks = webLinks;
+    this.created = created;
+  }
+
+  public TagInfo(String ref, String revision, Boolean canDelete, List<WebLinkInfo> webLinks) {
+    this(ref, revision, canDelete, webLinks, null);
+  }
+
+  public TagInfo(
+      String ref,
+      String revision,
+      String object,
+      String message,
+      GitPerson tagger,
+      Boolean canDelete,
+      List<WebLinkInfo> webLinks,
+      Timestamp created) {
+    this(ref, revision, canDelete, webLinks, created);
+    this.object = object;
+    this.message = message;
+    this.tagger = tagger;
+    this.webLinks = webLinks;
   }
 
   public TagInfo(
@@ -39,7 +67,7 @@ public class TagInfo extends RefInfo {
       GitPerson tagger,
       Boolean canDelete,
       List<WebLinkInfo> webLinks) {
-    this(ref, revision, canDelete, webLinks);
+    this(ref, revision, object, message, tagger, canDelete, webLinks, null);
     this.object = object;
     this.message = message;
     this.tagger = tagger;