Merge pull request #2492 from 0xProject/fix/instant/constant-polling

[Fix] Instant call destroyAsync on unmount

packages/asset-swapper/src/swap_quoter.ts

@@ -466,7 +466,8 @@ export class SwapQuoter {
      * Destroys any subscriptions or connections.
      */
     public async destroyAsync(): Promise<void> {
-        return this.orderbook.destroyAsync();
+        await this._protocolFeeUtils.destroyAsync();
+        await this.orderbook.destroyAsync();
     }
 
     /**

packages/instant/src/components/zero_ex_instant_provider.tsx

@@ -153,6 +153,9 @@ export class ZeroExInstantProvider extends React.PureComponent<ZeroExInstantProv
         if (this._swapQuoteHeartbeat) {
             this._swapQuoteHeartbeat.stop();
         }
+        const state = this._store.getState();
+        // tslint:disable-next-line: no-floating-promises
+        state.providerState.swapQuoter.destroyAsync();
     }
     public render(): React.ReactNode {
         return (