Replace sprockets/browserify with Webpack (#2617)

* Replace browserify with webpack

* Add react-intl-translations-manager

* Do not minify in development, add offline-plugin for ServiceWorker background cache updates

* Adjust tests and dependencies

* Fix production deployments

* Fix tests

* More optimizations

* Improve travis cache for npm stuff

* Re-run travis

* Add back support for custom.scss as before

* Remove offline-plugin and babili

* Fix issue with Immutable.List().unshift(...values) not working as expected

* Make travis load schema instead of running all migrations in sequence

* Fix missing React import in WarningContainer. Optimize rendering performance by using ImmutablePureComponent instead of
React.PureComponent. ImmutablePureComponent uses Immutable.is() to compare props. Replace dynamic callback bindings in
<UI />

* Add react definitions to places that use JSX

* Add Procfile.dev for running rails, webpack and streaming API at the same time

app/javascript/mastodon/features/compose/components/search.js

@@ -0,0 +1,82 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+import { defineMessages, injectIntl, FormattedMessage } from 'react-intl';
+
+const messages = defineMessages({
+  placeholder: { id: 'search.placeholder', defaultMessage: 'Search' }
+});
+
+class Search extends React.PureComponent {
+
+  constructor (props, context) {
+    super(props, context);
+    this.handleChange = this.handleChange.bind(this);
+    this.handleKeyDown = this.handleKeyDown.bind(this);
+    this.handleFocus = this.handleFocus.bind(this);
+    this.handleClear = this.handleClear.bind(this);
+  }
+
+  handleChange (e) {
+    this.props.onChange(e.target.value);
+  }
+
+  handleClear (e) {
+    e.preventDefault();
+
+    if (this.props.value.length > 0 || this.props.submitted) {
+      this.props.onClear();
+    }
+  }
+
+  handleKeyDown (e) {
+    if (e.key === 'Enter') {
+      e.preventDefault();
+      this.props.onSubmit();
+    }
+  }
+
+  noop () {
+
+  }
+
+  handleFocus () {
+    this.props.onShow();
+  }
+
+  render () {
+    const { intl, value, submitted } = this.props;
+    const hasValue = value.length > 0 || submitted;
+
+    return (
+      <div className='search'>
+        <input
+          className='search__input'
+          type='text'
+          placeholder={intl.formatMessage(messages.placeholder)}
+          value={value}
+          onChange={this.handleChange}
+          onKeyUp={this.handleKeyDown}
+          onFocus={this.handleFocus}
+        />
+
+        <div role='button' tabIndex='0' className='search__icon' onClick={this.handleClear}>
+          <i className={`fa fa-search ${hasValue ? '' : 'active'}`} />
+          <i aria-label={intl.formatMessage(messages.placeholder)} className={`fa fa-times-circle ${hasValue ? 'active' : ''}`} />
+        </div>
+      </div>
+    );
+  }
+
+}
+
+Search.propTypes = {
+  value: PropTypes.string.isRequired,
+  submitted: PropTypes.bool,
+  onChange: PropTypes.func.isRequired,
+  onSubmit: PropTypes.func.isRequired,
+  onClear: PropTypes.func.isRequired,
+  onShow: PropTypes.func.isRequired,
+  intl: PropTypes.object.isRequired
+};
+
+export default injectIntl(Search);