Move URL preview properties from RoomBubbleCellData in MXKRoomBubbleComponent.

Stop breaking up the bubble data for links now that vertical whitespace is added.

Riot/Modules/Room/CellData/RoomBubbleCellData.h

@@ -15,7 +15,6 @@
  */
 
 #import <MatrixKit/MatrixKit.h>
-@class URLPreviewData;
 
 extern NSString *const URLPreviewDidUpdateNotification;
 
@@ -81,16 +80,6 @@ typedef NS_ENUM(NSInteger, RoomBubbleCellDataTag)
  */
 @property(nonatomic, readonly) CGFloat additionalContentHeight;
 
-/**
- The data necessary to show a URL preview.
- */
-@property (nonatomic) URLPreviewData *urlPreviewData;
-
-/**
- Whether a URL preview should be displayed for this cell.
- */
-@property (nonatomic) BOOL showURLPreview;
-
 /**
  MXKeyVerification object associated to key verification event when using key verification by direct message.
  */