Bug 1688503 - nsFirstLetterFrame.cpp: do not use 'else' after 'return' r=sylvestre

Removed the 'else' statement to resolve clang-tidy warning.

Differential Revision: https://phabricator.services.mozilla.com/D103347

layout/generic/nsFirstLetterFrame.cpp

@@ -88,10 +88,9 @@ nsresult nsFirstLetterFrame::GetChildFrameContainingOffset(
   if (kid) {
     return kid->GetChildFrameContainingOffset(
         inContentOffset, inHint, outFrameContentOffset, outChildFrame);
-  } else {
-    return nsIFrame::GetChildFrameContainingOffset(
-        inContentOffset, inHint, outFrameContentOffset, outChildFrame);
   }
+  return nsIFrame::GetChildFrameContainingOffset(
+      inContentOffset, inHint, outFrameContentOffset, outChildFrame);
 }
 
 // Needed for non-floating first-letter frames and for the continuations