Respond to CR.

Signal/src/ViewControllers/ConversationView/ConversationViewItem.m

@@ -263,7 +263,7 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType)
 
 - (CGFloat)vSpacingWithPreviousLayoutItem:(ConversationViewItem *)previousLayoutItem
 {
-    OWSAssert(lastItem);
+    OWSAssert(previousLayoutItem);
 
     if (self.interaction.interactionType == OWSInteractionType_UnreadIndicator
         || previousLayoutItem.interaction.interactionType == OWSInteractionType_UnreadIndicator) {

Signal/src/ViewControllers/ConversationView/ConversationViewLayout.h

@@ -23,7 +23,7 @@ typedef NS_ENUM(NSInteger, ConversationViewLayoutAlignment) {
 
 - (ConversationViewLayoutAlignment)layoutAlignment;
 
-- (CGFloat)vSpacingWithPreviousLayoutItem:(id<ConversationViewLayoutItem>)lastLayoutItem;
+- (CGFloat)vSpacingWithPreviousLayoutItem:(id<ConversationViewLayoutItem>)previousLayoutItem;
 
 @end
 

Signal/src/ViewControllers/MessageDetailViewController.swift

@@ -40,6 +40,8 @@ class MessageDetailViewController: OWSViewController, MediaGalleryDataSourceDele
     var attachmentStream: TSAttachmentStream?
     var messageBody: String?
 
+    var conversationLayoutInfo: ConversationLayoutInfo
+
     private var contactShareViewHelper: ContactShareViewHelper
 
     // MARK: Initializers
@@ -57,6 +59,7 @@ class MessageDetailViewController: OWSViewController, MediaGalleryDataSourceDele
         self.mode = mode
         self.uiDatabaseConnection = OWSPrimaryStorage.shared().newDatabaseConnection()
         self.contactShareViewHelper = ContactShareViewHelper(contactsManager: contactsManager)
+        self.conversationLayoutInfo = ConversationLayoutInfo(thread: thread)
 
         super.init(nibName: nil, bundle: nil)
 
@@ -343,7 +346,6 @@ class MessageDetailViewController: OWSViewController, MediaGalleryDataSourceDele
         messageBubbleView.viewItem = viewItem
         messageBubbleView.cellMediaCache = NSCache()
         let conversationLayoutInfo = ConversationLayoutInfo(thread: thread)
-        conversationLayoutInfo.viewWidth = self.view.width()
         messageBubbleView.layoutInfo = conversationLayoutInfo
         messageBubbleView.configureViews()
         messageBubbleView.loadContent()