General react performance improvements (#2796)

* General React performance improvements

* Cleaned up unused props/state in PermaLinkView and PostFocusView

webapp/components/channel_view.jsx

@@ -11,6 +11,8 @@ import PostsViewContainer from 'components/posts_view_container.jsx';
 
 import ChannelStore from 'stores/channel_store.jsx';
 
+import * as Utils from 'utils/utils.jsx';
+
 export default class ChannelView extends React.Component {
     constructor(props) {
         super(props);
@@ -47,6 +49,17 @@ export default class ChannelView extends React.Component {
     componentWillReceiveProps(nextProps) {
         this.setState(this.getStateFromStores(nextProps));
     }
+    shouldComponentUpdate(nextProps, nextState) {
+        if (!Utils.areObjectsEqual(nextProps.params, this.props.params)) {
+            return true;
+        }
+
+        if (nextState.channelId !== this.state.channelId) {
+            return true;
+        }
+
+        return false;
+    }
     render() {
         return (
             <div
@@ -57,7 +70,7 @@ export default class ChannelView extends React.Component {
                 <ChannelHeader
                     channelId={this.state.channelId}
                 />
-                <PostsViewContainer profiles={this.props.profiles}/>
+                <PostsViewContainer/>
                 <div
                     className='post-create__container'
                     id='post-create'
@@ -72,6 +85,5 @@ ChannelView.defaultProps = {
 };
 
 ChannelView.propTypes = {
-    params: React.PropTypes.object.isRequired,
-    profiles: React.PropTypes.object
+    params: React.PropTypes.object.isRequired
 };