Clean up ahead of PR.

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -2788,6 +2788,9 @@ typedef NS_ENUM(NSInteger, MessagesRangeSizeMode) {
 
     DDLogVerbose(@"%@ %s", self.logTag, __PRETTY_FUNCTION__);
 
+    // External database modifications can't be converted into incremental updates,
+    // so rebuild everything.  This is expensive and usually isn't necessary, but
+    // there's no alternative.
     [self resetMappings];
 }
 

Signal/src/ViewControllers/HomeViewController.m

@@ -929,6 +929,9 @@ typedef NS_ENUM(NSInteger, CellState) { kArchiveState, kInboxState };
 
     DDLogVerbose(@"%@ %s", self.logTag, __PRETTY_FUNCTION__);
 
+    // External database modifications can't be converted into incremental updates,
+    // so rebuild everything.  This is expensive and usually isn't necessary, but
+    // there's no alternative.
     [self resetMappings];
 }