message: removed onError from state
diff: @@ -18,12 +18,12 @@ import React, { ComponentClass, Component, SFC } from 'react';
  type Props = {
  slackChannel: string;
  + onError?: (error: Error, errorInfo: string) => null;
  };
  type State = {
  error?: Error;
  errorInfo?: string;
  - onError?: (error: Error, errorInfo: string) => null;
  };
  const ErrorBoundary: ComponentClass<
  @@ -36,7 +36,6 @@ const ErrorBoundary: ComponentClass<
  this.state = {
  error: undefined,
  errorInfo: undefined,
  - onError: props.onError,
  };
  }
  @@ -46,8 +45,8 @@ const ErrorBoundary: ComponentClass<
  this.setState({ error, errorInfo });
  // Exposed for testing
  - if (this.state.onError) {
  - this.state.onError(error, errorInfo);
  + if (this.props.onError) {
  + this.props.onError(error, errorInfo);
  }
  }
  