Cancel operations on out of memory

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

@@ -234,7 +234,8 @@ class Core {
                         if (message != null)
                             db.message().setMessageError(message.id, Helper.formatThrowable(ex, true));
 
-                        if (ex instanceof MessageRemovedException ||
+                        if (ex instanceof OutOfMemoryError ||
+                                ex instanceof MessageRemovedException ||
                                 ex instanceof FolderNotFoundException ||
                                 ex instanceof IllegalArgumentException) {
                             Log.w("Unrecoverable");

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

@@ -213,7 +213,8 @@ public class ServiceSend extends LifecycleService {
                                     if (message != null)
                                         db.message().setMessageError(message.id, Helper.formatThrowable(ex));
 
-                                    if (ex instanceof MessageRemovedException ||
+                                    if (ex instanceof OutOfMemoryError ||
+                                            ex instanceof MessageRemovedException ||
                                             ex instanceof SendFailedException ||
                                             ex instanceof IllegalArgumentException) {
                                         Log.w("Unrecoverable");