Fix isInternalUrl for subdomain support

Refactor / reduce plumbing

app/components/Alert.js

@@ -0,0 +1,36 @@
+// @flow
+import * as React from 'react';
+import { observer } from 'mobx-react';
+import Flex from 'shared/components/Flex';
+import styled from 'styled-components';
+
+type Props = {
+  children: React.Node,
+  type?: 'info' | 'success' | 'warning' | 'danger' | 'offline',
+};
+
+@observer
+class Alert extends React.Component<Props> {
+  defaultProps = {
+    type: 'info',
+  };
+
+  render() {
+    return (
+      <Container align="center" justify="center" type={this.props.type}>
+        {this.props.children}
+      </Container>
+    );
+  }
+}
+
+const Container = styled(Flex)`
+  height: $headerHeight;
+  color: #ffffff;
+  font-size: 14px;
+  line-height: 1;
+
+  background-color: ${({ theme, type }) => theme.color[type]};
+`;
+
+export default Alert;