save a few ms on send, hoist async dispatch to caller, and use it for clearing draft

Signal/src/ViewControllers/ConversationView/ConversationInputToolbar.m

@@ -222,17 +222,11 @@ const CGFloat kMaxTextViewHeight = 98;
     // Momentarily switch to a non-default keyboard, else reloadInputViews
     // will not affect the displayed keyboard. In practice this isn't perceptable to the user.
     // The alternative would be to dismiss-and-pop the keyboard, but that can cause a more pronounced animation.
-    //
-    // This is surprisingly expensive (~5ms), so we do it async, *after* the message is rendered.
-    dispatch_async(dispatch_get_main_queue(), ^{
-        [BenchManager benchWithTitle:@"toggleDefaultKeyboard" block:^{
-            self.inputTextView.keyboardType = UIKeyboardTypeNumbersAndPunctuation;
-            [self.inputTextView reloadInputViews];
-
-            self.inputTextView.keyboardType = UIKeyboardTypeDefault;
-            [self.inputTextView reloadInputViews];
-        }];
-    });
+    self.inputTextView.keyboardType = UIKeyboardTypeNumbersAndPunctuation;
+    [self.inputTextView reloadInputViews];
+
+    self.inputTextView.keyboardType = UIKeyboardTypeDefault;
+    [self.inputTextView reloadInputViews];
 }
 
 - (void)setQuotedReply:(nullable OWSQuotedReplyModel *)quotedReply

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -3898,10 +3898,21 @@ typedef enum : NSUInteger {
 
     [self messageWasSent:message];
 
-    if (updateKeyboardState) {
-        [self.inputToolbar toggleDefaultKeyboard];
-    }
-    [self.inputToolbar clearTextMessageAnimated:YES];
+
+    dispatch_async(dispatch_get_main_queue(), ^{
+        [BenchManager benchWithTitle:@"toggleDefaultKeyboard"
+                               block:^{
+                                   if (updateKeyboardState) {
+                                       [self.inputToolbar toggleDefaultKeyboard];
+                                   }
+                               }];
+
+        [BenchManager benchWithTitle:@"clearTextMessageAnimated"
+                               block:^{
+                                   [self.inputToolbar clearTextMessageAnimated:YES];
+                               }];
+    });
+
     [self clearDraft];
     if (didAddToProfileWhitelist) {
         [self.conversationViewModel ensureDynamicInteractions];