Pull up additionalRefsNames from RefDirectory to RefDatabase

This enables to reuse this constant in all RefDatabase implementations.

Change-Id: I13d8fb780de24f71e005b698965fb5bcdbf3c728

org.eclipse.jgit/.settings/.api_filters

@@ -8,4 +8,12 @@
             </message_arguments>
         </filter>
     </resource>
+    <resource path="src/org/eclipse/jgit/lib/RefDatabase.java" type="org.eclipse.jgit.lib.RefDatabase">
+        <filter id="336658481">
+            <message_arguments>
+                <message_argument value="org.eclipse.jgit.lib.RefDatabase"/>
+                <message_argument value="additionalRefsNames"/>
+            </message_arguments>
+        </filter>
+    </resource>
 </component>

org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/RefDirectory.java

@@ -108,11 +108,6 @@ public class RefDirectory extends RefDatabase {
 	/** If in the header, denotes the file has peeled data. */
 	public static final String PACKED_REFS_PEELED = " peeled"; //$NON-NLS-1$
 
-	/** The names of the additional refs supported by this class */
-	private static final String[] additionalRefsNames = new String[] {
-			Constants.MERGE_HEAD, Constants.FETCH_HEAD, Constants.ORIG_HEAD,
-			Constants.CHERRY_PICK_HEAD };
-
 	@SuppressWarnings("boxing")
 	private static final List<Integer> RETRY_SLEEP_MS =
 			Collections.unmodifiableList(Arrays.asList(0, 100, 200, 400, 800, 1600));

org.eclipse.jgit/src/org/eclipse/jgit/lib/RefDatabase.java

@@ -68,6 +68,15 @@ public abstract class RefDatabase {
 	 */
 	public static final String ALL = "";//$NON-NLS-1$
 
+	/**
+	 * The names of additional refs
+	 *
+	 * @since 6.5
+	 */
+	protected static final String[] additionalRefsNames = new String[] {
+			Constants.MERGE_HEAD, Constants.FETCH_HEAD, Constants.ORIG_HEAD,
+			Constants.CHERRY_PICK_HEAD, Constants.REVERT_HEAD };
+
 	/**
 	 * Initialize a new reference database at this location.
 	 *