Bug 1508472 - Part 1: First batch of comment fix-ups in preparation for the tree reformat r=sylvestre

This is a best effort attempt at ensuring that the adverse impact of
reformatting the entire tree over the comments would be minimal.  I've used a
combination of strategies including disabling of formatting, some manual
formatting and some changes to formatting to work around some clang-format
limitations.

Differential Revision: https://phabricator.services.mozilla.com/D13046

dom/html/HTMLTableElement.cpp

@@ -19,7 +19,7 @@ NS_IMPL_NS_NEW_HTML_ELEMENT(Table)
 namespace mozilla {
 namespace dom {
 
-/* ------------------------------ TableRowsCollection -------------------------------- */
+/* ------------------------- TableRowsCollection --------------------------- */
 /**
  * This class provides a late-bound collection of rows in a table.
  * mParent is NOT ref-counted to avoid circular references