Fix downloading LFS Object fails behind proxy

When downloading LFS objects also accept response code 203 as successful
download. This response may be seen when downloading via a proxy.

Bug: 563022
Change-Id: Iee85fdb451b33369d08859872e5bfc2a67dffa6d
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.lfs/src/org/eclipse/jgit/lfs/SmudgeFilter.java

@@ -133,7 +133,8 @@ public class SmudgeFilter extends FilterCommand {
 								.toRequest(Protocol.OPERATION_DOWNLOAD, res))
 						.getBytes(UTF_8));
 		int responseCode = lfsServerConn.getResponseCode();
-		if (responseCode != HttpConnection.HTTP_OK) {
+		if (!(responseCode == HttpConnection.HTTP_OK
+				|| responseCode == HttpConnection.HTTP_NOT_AUTHORITATIVE)) {
 			throw new IOException(
 					MessageFormat.format(LfsText.get().serverFailure,
 							lfsServerConn.getURL(),

org.eclipse.jgit/.settings/.api_filters

@@ -7,5 +7,11 @@
                 <message_argument value="HTTP_11_MOVED_PERM"/>
             </message_arguments>
         </filter>
+        <filter id="403767336">
+            <message_arguments>
+                <message_argument value="org.eclipse.jgit.transport.http.HttpConnection"/>
+                <message_argument value="HTTP_NOT_AUTHORITATIVE"/>
+            </message_arguments>
+        </filter>
     </resource>
 </component>

org.eclipse.jgit/src/org/eclipse/jgit/transport/http/HttpConnection.java

@@ -40,6 +40,12 @@ public interface HttpConnection {
 	 */
 	int HTTP_OK = java.net.HttpURLConnection.HTTP_OK;
 
+	/**
+	 * @see HttpURLConnection#HTTP_NOT_AUTHORITATIVE
+	 * @since 5.8
+	 */
+	int HTTP_NOT_AUTHORITATIVE = java.net.HttpURLConnection.HTTP_NOT_AUTHORITATIVE;
+
 	/**
 	 * @see HttpURLConnection#HTTP_MOVED_PERM
 	 * @since 4.7