MXKRoomBubbleCellData: Add convenient isAttachment property.

Riot/Modules/MatrixKit/Models/Room/MXKRoomBubbleCellData.m

@@ -724,6 +724,27 @@
     return NO;
 }
 
+- (BOOL)isAttachment
+{
+    if (!self.attachment)
+    {
+        return NO;
+    }
+    
+    if (!attachment.contentURL || !attachment.contentInfo) {
+        return NO;
+    }
+    
+    switch (self.attachment.type) {
+        case MXKAttachmentTypeFile:
+        case MXKAttachmentTypeAudio:
+        case MXKAttachmentTypeVoiceMessage:
+            return YES;
+        default:
+            return NO;
+    }
+}
+
 - (void)setMaxTextViewWidth:(CGFloat)inMaxTextViewWidth
 {
     // Check change

Riot/Modules/MatrixKit/Models/Room/MXKRoomBubbleCellDataStoring.h

@@ -147,6 +147,11 @@
  */
 @property (nonatomic) BOOL isAttachmentWithIcon;
 
+/**
+ YES when the bubble correspond to an attachment (audio, file...).
+ */
+@property (nonatomic, readonly) BOOL isAttachment;
+
 /**
  Flag that indicates that self.attributedTextMessage will be not nil.
  This avoids the computation of self.attributedTextMessage that can take time.