Avoid using small objects where possible

src/matrix/storage/idb/QueryTarget.ts

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import {iterateCursor, reqAsPromise} from "./utils";
+import {iterateCursor, DONE, NOT_DONE, reqAsPromise} from "./utils";
 
 type Reducer<A,B> = (acc: B, val: A) => B
 
@@ -101,7 +101,7 @@ export class QueryTarget<T> {
         const results: T[] = [];
         await iterateCursor<T>(cursor, (value) => {
             results.push(value);
-            return {done: false};
+            return NOT_DONE;
         });
         return results;
     }
@@ -127,7 +127,7 @@ export class QueryTarget<T> {
         let maxKey: IDBValidKey | undefined;
         await iterateCursor(cursor, (_, key) => {
             maxKey = key;
-            return {done: true};
+            return DONE;
         });
         return maxKey;
     }
@@ -191,7 +191,7 @@ export class QueryTarget<T> {
         const cursor = this._openCursor(range, direction);
         return iterateCursor<T>(cursor, (value) => {
             reducedValue = reducer(reducedValue, value);
-            return {done: false};
+            return NOT_DONE;
         });
     }
 

src/matrix/storage/idb/export.ts

@@ -14,11 +14,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { iterateCursor, txnAsPromise } from "./utils";
+import { iterateCursor, NOT_DONE, txnAsPromise } from "./utils";
 import { STORE_NAMES } from "../common";
 
 export async function exportSession(db: IDBDatabase): Promise<{ [storeName : string] : any }> {
-    const NOT_DONE = {done: false};
     const txn = db.transaction(STORE_NAMES, "readonly");
     const data = {};
     await Promise.all(STORE_NAMES.map(async name => {

src/matrix/storage/idb/schema.ts

@@ -1,4 +1,4 @@
-import {iterateCursor, reqAsPromise} from "./utils";
+import {iterateCursor, NOT_DONE, reqAsPromise} from "./utils";
 import {RoomMember, EVENT_TYPE as MEMBER_EVENT_TYPE} from "../../room/members/RoomMember.js";
 import {RoomMemberStore} from "./stores/RoomMemberStore";
 import {RoomStateEntry} from "./stores/RoomStateStore";
@@ -21,8 +21,6 @@ export const schema = [
 ];
 // TODO: how to deal with git merge conflicts of this array?
 
-const NOT_DONE = {done:false};
-
 // TypeScript note: for now, do not bother introducing interfaces / alias
 // for old schemas. Just take them as `any`. 
 

src/matrix/storage/idb/utils.ts

@@ -18,6 +18,9 @@ limitations under the License.
 import { IDBRequestError } from "./error";
 import { StorageError } from "../common";
 
+export const NOT_DONE = { done: false };
+export const DONE = { done: true };
+
 let needsSyncPromise = false;
 
 /* should be called on legacy platforms to see