Deprecate methods for handling non-canonical BDF.

bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfMessageValidator.java

@@ -31,6 +31,12 @@ public abstract class BdfMessageValidator implements MessageValidator {
 	protected final Clock clock;
 	protected final boolean canonical;
 
+	/**
+	 * Transitional alternative to
+	 * {@link #BdfMessageValidator(ClientHelper, MetadataEncoder, Clock)} that
+	 * accepts messages in non-canonical form, for backward compatibility.
+	 */
+	@Deprecated
 	protected BdfMessageValidator(ClientHelper clientHelper,
 			MetadataEncoder metadataEncoder, Clock clock, boolean canonical) {
 		this.clientHelper = clientHelper;

bramble-api/src/main/java/org/briarproject/bramble/api/client/ClientHelper.java

@@ -49,6 +49,15 @@ public interface ClientHelper {
 	BdfList getMessageAsList(Transaction txn, MessageId m) throws DbException,
 			FormatException;
 
+	/**
+	 * Transitional alternative to
+	 * {@link #getMessageAsList(Transaction, MessageId)} that allows the
+	 * message to be in non-canonical form, for backward compatibility.
+	 *
+	 * @param canonical True if the message must be in canonical form (a
+	 * {@link FormatException} will be thrown if it's not.
+	 */
+	@Deprecated
 	BdfList getMessageAsList(Transaction txn, MessageId m, boolean canonical)
 			throws DbException, FormatException;
 
@@ -109,6 +118,14 @@ public interface ClientHelper {
 
 	BdfList toList(Message m) throws FormatException;
 
+	/**
+	 * Transitional alternative to {@link #toList(Message)} that allows the
+	 * message to be in non-canonical form, for backward compatibility.
+	 *
+	 * @param canonical True if the message must be in canonical form (a
+	 * {@link FormatException} will be thrown if it's not.
+	 */
+	@Deprecated
 	BdfList toList(Message m, boolean canonical) throws FormatException;
 
 	BdfList toList(Author a);

bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfReaderFactory.java

@@ -9,6 +9,12 @@ public interface BdfReaderFactory {
 
 	BdfReader createReader(InputStream in);
 
+	/**
+	 * Transitional alternative to {@link #createReader(InputStream)} that
+	 * can create a reader that accepts non-canonical input, for backward
+	 * compatibility.
+	 */
+	@Deprecated
 	BdfReader createReader(InputStream in, boolean canonical);
 
 	BdfReader createReader(InputStream in, int nestedLimit,

bramble-core/src/main/java/org/briarproject/bramble/properties/TransportPropertyManagerImpl.java

@@ -311,6 +311,7 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 				if (latest == null) {
 					merged = new TransportProperties(p);
 					Iterator<String> it = merged.values().iterator();
+					//noinspection Java8CollectionRemoveIf
 					while (it.hasNext()) {
 						if (isNullOrEmpty(it.next())) it.remove();
 					}