Remove isTracked field on token in favor of trackedTimestamp

packages/website/ts/components/dialogs/track_token_confirmation_dialog.tsx

@@ -1,5 +1,6 @@
 import Dialog from 'material-ui/Dialog';
 import FlatButton from 'material-ui/FlatButton';
+import * as moment from 'moment';
 import * as React from 'react';
 import { Blockchain } from 'ts/blockchain';
 import { TrackTokenConfirmation } from 'ts/components/track_token_confirmation';
@@ -73,12 +74,13 @@ export class TrackTokenConfirmationDialog extends React.Component<
         this.setState({
             isAddingTokenToTracked: true,
         });
+        const currentTimestamp = moment().unix();
         for (const token of this.props.tokens) {
             const newTokenEntry = {
                 ...token,
+                trackedTimestamp: currentTimestamp,
             };
 
-            newTokenEntry.isTracked = true;
             trackedTokenStorage.addTrackedTokenToUser(this.props.userAddress, this.props.networkId, newTokenEntry);
             this.props.dispatcher.updateTokenByAddress([newTokenEntry]);
         }