docs: public List<Task> allTasks() throws DocumentStoreException {
          int nDocs = this.mDocumentStore.database().getDocumentCount();
          List<DocumentRevision> all = this.mDocumentStore.database().read(0, nDocs, true);
          List<Task> tasks = new ArrayList<Task>();
  
          // Filter all documents down to those of type Task.
          for(DocumentRevision rev : all) {
              Task t = Task.fromRevision(rev);
              if (t != null) {
                  tasks.add(t);
              }
          }
  
          return tasks;
      }