Limit number of pushed add/delete

app/src/main/java/eu/faircode/email/Core.java

@@ -150,7 +150,7 @@ class Core {
     private static final long LOCAL_RETRY_DELAY = 5 * 1000L; // milliseconds
     private static final int TOTAL_RETRY_MAX = LOCAL_RETRY_MAX * 5;
     private static final int MAX_PREVIEW = 5000; // characters
-    private static final int MAX_FETCH = 100;
+    static final int MAX_FETCH = 100;
 
     static void processOperations(
             Context context,

app/src/main/java/eu/faircode/email/ServiceSynchronize.java

@@ -1166,10 +1166,13 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                                         try {
                                             db.beginTransaction();
 
-                                            for (Message imessage : e.getMessages()) {
-                                                long uid = ifolder.getUID(imessage);
-                                                EntityOperation.queue(ServiceSynchronize.this, folder, EntityOperation.FETCH, uid);
-                                            }
+                                            if (e.getMessages().length > Core.MAX_FETCH)
+                                                EntityOperation.sync(ServiceSynchronize.this, folder.id, false);
+                                            else
+                                                for (Message imessage : e.getMessages()) {
+                                                    long uid = ifolder.getUID(imessage);
+                                                    EntityOperation.queue(ServiceSynchronize.this, folder, EntityOperation.FETCH, uid);
+                                                }
 
                                             db.setTransactionSuccessful();
                                         } finally {
@@ -1195,10 +1198,13 @@ public class ServiceSynchronize extends ServiceBase implements SharedPreferences
                                         try {
                                             db.beginTransaction();
 
-                                            for (Message imessage : e.getMessages()) {
-                                                long uid = ifolder.getUID(imessage);
-                                                EntityOperation.queue(ServiceSynchronize.this, folder, EntityOperation.FETCH, uid, true);
-                                            }
+                                            if (e.getMessages().length > Core.MAX_FETCH)
+                                                EntityOperation.sync(ServiceSynchronize.this, folder.id, false);
+                                            else
+                                                for (Message imessage : e.getMessages()) {
+                                                    long uid = ifolder.getUID(imessage);
+                                                    EntityOperation.queue(ServiceSynchronize.this, folder, EntityOperation.FETCH, uid, true);
+                                                }
 
                                             db.setTransactionSuccessful();
                                         } finally {