Respond to CR.

Signal/src/ViewControllers/ConversationView/Cells/OWSMessageCell.m

@@ -268,8 +268,8 @@ NS_ASSUME_NONNULL_BEGIN
         return NO;
     }
 
-    TSIncomingMessage *incomingMessage = (TSIncomingMessage *)self.viewItem.interaction;
-    TSThread *authorThread = [TSContactThread getOrCreateThreadWithContactId:incomingMessage.authorId];
+    OWSAssertDebug(self.viewItem.incomingMessageAuthorThread);
+    TSThread *authorThread = self.viewItem.incomingMessageAuthorThread;
     UIImage *_Nullable authorAvatarImage =
         [OWSAvatarBuilder buildImageForThread:authorThread diameter:self.avatarSize contactsManager:contactsManager];
     self.avatarView.image = authorAvatarImage;

Signal/src/ViewControllers/ConversationView/ConversationViewItem.h

@@ -33,6 +33,7 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType);
 @class TSAttachmentPointer;
 @class TSAttachmentStream;
 @class TSInteraction;
+@class TSThread;
 @class YapDatabaseReadTransaction;
 
 // This is a ViewModel for cells in the conversation view.
@@ -45,6 +46,8 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType);
 @interface ConversationViewItem : NSObject <ConversationViewLayoutItem, OWSAudioPlayerDelegate>
 
 @property (nonatomic, readonly) TSInteraction *interaction;
+@property (nonatomic, nullable, readonly) TSThread *incomingMessageAuthorThread;
+
 @property (nonatomic, readonly, nullable) OWSQuotedReplyModel *quotedReply;
 
 @property (nonatomic, readonly) BOOL isGroupThread;

Signal/src/ViewControllers/ConversationView/ConversationViewItem.m

@@ -63,12 +63,11 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType)
 @property (nonatomic, nullable) DisplayableText *displayableBodyText;
 @property (nonatomic, nullable) DisplayableText *displayableQuotedText;
 @property (nonatomic, nullable) OWSQuotedReplyModel *quotedReply;
-@property (nonatomic, readonly, nullable) NSString *quotedAttachmentMimetype;
-@property (nonatomic, readonly, nullable) NSString *quotedRecipientId;
 @property (nonatomic, nullable) TSAttachmentStream *attachmentStream;
 @property (nonatomic, nullable) TSAttachmentPointer *attachmentPointer;
 @property (nonatomic, nullable) ContactShareViewModel *contactShare;
 @property (nonatomic) CGSize mediaSize;
+@property (nonatomic, nullable) TSThread *incomingMessageAuthorThread;
 
 @end
 
@@ -94,6 +93,9 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType)
     _interaction = interaction;
     _isGroupThread = isGroupThread;
     _conversationStyle = conversationStyle;
+    _incomingMessageAuthorThread = ([interaction isKindOfClass:[TSIncomingMessage class]]
+            ? [TSContactThread getOrCreateThreadWithContactId:((TSIncomingMessage *)interaction).authorId]
+            : nil);
 
     [self ensureViewState:transaction];
 
@@ -105,6 +107,9 @@ NSString *NSStringForOWSMessageCellType(OWSMessageCellType cellType)
     OWSAssertDebug(interaction);
 
     _interaction = interaction;
+    _incomingMessageAuthorThread = ([interaction isKindOfClass:[TSIncomingMessage class]]
+            ? [TSContactThread getOrCreateThreadWithContactId:((TSIncomingMessage *)interaction).authorId]
+            : nil);
 
     self.hasViewState = NO;
     self.messageCellType = OWSMessageCellType_Unknown;

SignalMessaging/utils/OWSAvatarBuilder.m

@@ -221,6 +221,8 @@ typedef void (^OWSAvatarDrawBlock)(CGContextRef context);
                                        context:nil]
                     .size;
         }
+    } else {
+        OWSFailDebug(@"Text has invalid bounds.");
     }
 
     CGPoint drawPoint = CGPointMake((diameter - textSize.width) * 0.5f, (diameter - textSize.height) * 0.5f);