Don't write messages without (partial) body to database

Opening such messages during download will display "No text" and (probably
due to a bug) might lead to the synchronization process being aborted. Instead
of fixing the UI issue we now don't write these incomplete messages to the
database. This has the potential to massively speed up the sync process. But
it will take longer for messages to show up in the message list, especially
with slow connections.

k9mail/src/main/java/com/fsck/k9/controller/MessagingController.java

@@ -1294,7 +1294,7 @@ public class MessagingController implements Runnable {
                 Log.d(K9.LOG_TAG, "SYNC: About to fetch " + unsyncedMessages.size() + " unsynced messages for folder " + folder);
 
 
-            fetchUnsyncedMessages(account, remoteFolder, localFolder, unsyncedMessages, smallMessages, largeMessages, progress, todo, fp);
+            fetchUnsyncedMessages(account, remoteFolder, unsyncedMessages, smallMessages, largeMessages, progress, todo, fp);
 
             String updatedPushState = localFolder.getPushState();
             for (Message message : unsyncedMessages) {
@@ -1442,7 +1442,6 @@ public class MessagingController implements Runnable {
     }
 
     private <T extends Message> void fetchUnsyncedMessages(final Account account, final Folder<T> remoteFolder,
-                                       final LocalFolder localFolder,
                                        List<T> unsyncedMessages,
                                        final List<Message> smallMessages,
                                        final List<Message> largeMessages,
@@ -1453,18 +1452,12 @@ public class MessagingController implements Runnable {
 
         final Date earliestDate = account.getEarliestPollDate();
 
-        /*
-         * Messages to be batch written
-         */
-        final List<Message> chunk = new ArrayList<Message>(UNSYNC_CHUNK_SIZE);
-
         remoteFolder.fetch(unsyncedMessages, fp,
         new MessageRetrievalListener<T>() {
             @Override
             public void messageFinished(T message, int number, int ofTotal) {
                 try {
                     if (message.isSet(Flag.DELETED) || message.olderThan(earliestDate)) {
-
                         if (K9.DEBUG) {
                             if (message.isSet(Flag.DELETED)) {
                                 Log.v(K9.LOG_TAG, "Newly downloaded message " + account + ":" + folder + ":" + message.getUid()
@@ -1487,24 +1480,6 @@ public class MessagingController implements Runnable {
                     } else {
                         smallMessages.add(message);
                     }
-
-                    // And include it in the view
-                    if (message.getSubject() != null && message.getFrom() != null) {
-                        /*
-                         * We check to make sure that we got something worth
-                         * showing (subject and from) because some protocols
-                         * (POP) may not be able to give us headers for
-                         * ENVELOPE, only size.
-                         */
-
-                        // keep message for delayed storing
-                        chunk.add(message);
-
-                        if (chunk.size() >= UNSYNC_CHUNK_SIZE) {
-                            writeUnsyncedMessages(chunk, localFolder, account, folder);
-                            chunk.clear();
-                        }
-                    }
                 } catch (Exception e) {
                     Log.e(K9.LOG_TAG, "Error while storing downloaded message.", e);
                     addErrorMessage(account, null, e);
@@ -1520,48 +1495,8 @@ public class MessagingController implements Runnable {
             }
 
         });
-        if (!chunk.isEmpty()) {
-            writeUnsyncedMessages(chunk, localFolder, account, folder);
-            chunk.clear();
-        }
     }
 
-    /**
-     * Actual storing of messages
-     *
-     * <br>
-     * FIXME: <strong>This method should really be moved in the above MessageRetrievalListener once {@link MessageRetrievalListener#messagesFinished(int)} is properly invoked by various stores</strong>
-     *
-     * @param messages Never <code>null</code>.
-     * @param localFolder
-     * @param account
-     * @param folder
-     */
-    private void writeUnsyncedMessages(final List<Message> messages, final LocalFolder localFolder, final Account account, final String folder) {
-        if (K9.DEBUG) {
-            Log.v(K9.LOG_TAG, "Batch writing " + Integer.toString(messages.size()) + " messages");
-        }
-        try {
-            // Store the new message locally
-            localFolder.appendMessages(messages);
-
-            for (final Message message : messages) {
-                final LocalMessage localMessage = localFolder.getMessage(message.getUid());
-                syncFlags(localMessage, message);
-                if (K9.DEBUG)
-                    Log.v(K9.LOG_TAG, "About to notify listeners that we got a new unsynced message "
-                          + account + ":" + folder + ":" + message.getUid());
-                for (final MessagingListener l : getListeners()) {
-                    l.synchronizeMailboxAddOrUpdateMessage(account, folder, localMessage);
-                }
-            }
-        } catch (final Exception e) {
-            Log.e(K9.LOG_TAG, "Error while storing downloaded message.", e);
-            addErrorMessage(account, null, e);
-        }
-    }
-
-
     private boolean shouldImportMessage(final Account account, final String folder, final Message message, final AtomicInteger progress, final Date earliestDate) {
 
         if (account.isSearchByDateCapable() && message.olderThan(earliestDate)) {