LogCommand.all(), peel references before using them

Problem:
LogCommand.all() throws an IncorrectObjectTypeException when
there are tag references, and the repository does not contain
the file "packed-refs". It seems that the references were not properly
peeled before being added to the markStart() method.

Solution:
Call getRepository().peel() on every Ref that has isPeeled()==false
in LogCommand.all() .

Added test case for LogCommand.all() on repo with a tag.

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 2. I have the rights to donate the content to Eclipse,
 3. I contribute the content under the EDL

Bug: 402025
Change-Id: Idb8881eeb6ccce8530f2837b25296e8e83636eb7

org.eclipse.jgit.test/tst/org/eclipse/jgit/api/LogCommandTest.java

@@ -51,6 +51,7 @@ import java.util.Iterator;
 import java.util.List;
 
 import org.eclipse.jgit.junit.RepositoryTestCase;
+import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.junit.Test;
@@ -89,6 +90,30 @@ public class LogCommandTest extends RepositoryTestCase {
 		assertFalse(log.hasNext());
 	}
 
+    @Test
+    public void logAllCommitsWithTag() throws Exception {
+		List<RevCommit> commits = new ArrayList<RevCommit>();
+		Git git = Git.wrap(db);
+
+		writeTrashFile("Test.txt", "Hello world");
+		git.add().addFilepattern("Test.txt").call();
+		commits.add(git.commit().setMessage("initial commit").call());
+
+		TagCommand tagCmd = git.tag();
+		tagCmd.setName("tagname");
+		tagCmd.setObjectId(commits.get(0));
+		tagCmd.setTagger(new PersonIdent(db));
+		Ref tag = tagCmd.call();
+
+		Iterator<RevCommit> log = git.log().all().call().iterator();
+		assertTrue(log.hasNext());
+		RevCommit commit = log.next();
+		tag = db.peel(tag);
+
+		assertEquals(commit.getName(), tag.getPeeledObjectId().getName());
+		assertTrue(commits.contains(commit));
+	}
+
 	private List<RevCommit> createCommits(Git git) throws Exception {
 		List<RevCommit> commits = new ArrayList<RevCommit>();
 		writeTrashFile("Test.txt", "Hello world");

org.eclipse.jgit/src/org/eclipse/jgit/api/LogCommand.java

@@ -239,6 +239,8 @@ public class LogCommand extends GitCommand<Iterable<RevCommit>> {
 	 */
 	public LogCommand all() throws IOException {
 		for (Ref ref : getRepository().getAllRefs().values()) {
+			if(!ref.isPeeled())
+				ref = getRepository().peel(ref);
 			ObjectId objectId = ref.getPeeledObjectId();
 			if (objectId == null)
 				objectId = ref.getObjectId();