Do not update state when the component is unmounted

Summary:
Bug:

{F176561921}

Reviewed By: danielbuechele

Differential Revision: D16763611

fbshipit-source-id: 93b95877f4818a9d2b2c7ba1b27eabaec41d4e95

src/chrome/ShareSheet.tsx

@@ -148,6 +148,7 @@ export default class ShareSheet extends Component<Props, State> {
       }
       this.props.logger.trackTimeSince(mark, 'export:url-success');
     } catch (e) {
+      if (!this.state.runInBackground) {
         const str = e instanceof Error ? e.toString() : e;
         this.setState({
           result: {
@@ -155,6 +156,7 @@ export default class ShareSheet extends Component<Props, State> {
             error: str,
           },
         });
+      }
       this.props.logger.trackTimeSince(mark, 'export:url-error');
     }
   }

src/chrome/ShareSheetExportFile.tsx

@@ -140,7 +140,9 @@ export default class ShareSheetExportFile extends Component<Props, State> {
       this.setState({errorArray, result: {success: true, error: null}});
       this.props.logger.trackTimeSince(mark, 'export:file-success');
     } catch (err) {
+      if (!this.state.runInBackground) {
         this.setState({errorArray: [], result: {success: false, error: err}});
+      }
       this.props.logger.trackTimeSince(mark, 'export:file-error');
     }
   }