Fixes bug where "The upload failed." error message shows up when media upload is canceled intentionally.

app/src/main/java/com/keylesspalace/tusky/ComposeActivity.java

@@ -1044,8 +1044,8 @@ public class ComposeActivity extends BaseActivity implements ComposeOptionsFragm
 
             @Override
             public void onFailure(Call<Media> call, Throwable t) {
-                Log.d(TAG, t.getMessage());
-                onUploadFailure(item, false);
+                Log.d(TAG, "Upload request failed. " + t.getMessage());
+                onUploadFailure(item, call.isCanceled());
             }
         });
     }
@@ -1079,8 +1079,11 @@ public class ComposeActivity extends BaseActivity implements ComposeOptionsFragm
         if (finishingUploadDialog != null) {
             finishingUploadDialog.cancel();
         }
+        if (!isCanceled) {
+            // If it is canceled, it's already been removed, otherwise do it.
             removeMediaFromQueue(item);
         }
+    }
 
     private void cancelReadyingMedia(QueuedMedia item) {
         if (item.readyStage == QueuedMedia.ReadyStage.UPLOADING) {