PLT-4860 Make ProfilePopover into it's own component and use it consistently everywhere (#4701)

* PLT-4860 - Use same User Popover everywhere.

Refactor out the ProfilePopover into it's own component and give it the
union of all the features of the previous two implementations, and make
sure all the necessary data for it to work consistently everywhere is
provided through the props wherever it is used.

* Don't show popover for webhook posts in main view.

* No popover on RHS when it's a webhook post.

* Fix style.

* Don't send in user when it's a system message.

* Fix some duplication of code.

webapp/components/post_view/components/post.jsx

@@ -194,9 +194,18 @@ export default class Post extends React.Component {
                 src={PostUtils.getProfilePicSrcForPost(post, timestamp)}
                 status={status}
                 user={this.props.user}
+                isBusy={this.props.isBusy}
             />
         );
 
+        if (post.props && post.props.from_webhook) {
+            profilePic = (
+                <ProfilePicture
+                    src={PostUtils.getProfilePicSrcForPost(post, timestamp)}
+                />
+            );
+        }
+
         if (PostUtils.isSystemMessage(post)) {
             profilePic = (
                 <span
@@ -215,13 +224,22 @@ export default class Post extends React.Component {
         if (this.props.compactDisplay) {
             compactClass = 'post--compact';
 
-            profilePic = (
-                <ProfilePicture
-                    src=''
-                    status={status}
-                    user={this.props.user}
-                />
-            );
+            if (post.props && post.props.from_webhook) {
+                profilePic = (
+                    <ProfilePicture
+                        src=''
+                        status={status}
+                        isBusy={this.props.isBusy}
+                        user={this.props.user}
+                    />
+                );
+            } else {
+                profilePic = (
+                    <ProfilePicture
+                        src=''
+                    />
+                );
+            }
         }
 
         const profilePicContainer = (<div className='post__img'>{profilePic}</div>);

webapp/components/post_view/components/post_header.jsx

@@ -40,6 +40,14 @@ export default class PostHeader extends React.Component {
                         disablePopover={true}
                     />
                 );
+            } else {
+                userProfile = (
+                    <UserProfile
+                        user={this.props.user}
+                        displayNameType={this.props.displayNameType}
+                        disablePopover={true}
+                    />
+                );
             }
 
             botIndicator = <li className='bot-indicator'>{Constants.BOT_NAME}</li>;