Bug 1497480 - Part 2: Make spellchecking to work in ShadowDOM after anchor navigates away from it; r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D9543

--HG--
extra : moz-landing-system : lando

extensions/spellcheck/src/mozInlineSpellChecker.cpp

@@ -86,9 +86,6 @@ using namespace mozilla::dom;
 #define INLINESPELL_STARTED_TOPIC "inlineSpellChecker-spellCheck-started"
 #define INLINESPELL_ENDED_TOPIC "inlineSpellChecker-spellCheck-ended"
 
-static bool ContentIsDescendantOf(nsINode* aPossibleDescendant,
-                                    nsINode* aPossibleAncestor);
-
 static const char kMaxSpellCheckSelectionSize[] =
   "extensions.spellcheck.inline.max-misspellings";
 static const PRTime kMaxSpellCheckTimeInUsec =
@@ -228,7 +225,8 @@ mozInlineSpellStatus::InitForNavigation(
     return NS_ERROR_FAILURE;
   }
   // the anchor node might not be in the DOM anymore, check
-  if (root && aOldAnchorNode && ! ContentIsDescendantOf(aOldAnchorNode, root)) {
+  if (root && aOldAnchorNode &&
+      !nsContentUtils::ContentIsShadowIncludingDescendantOf(aOldAnchorNode, root)) {
     *aContinue = false;
     return NS_OK;
   }
@@ -1728,24 +1726,6 @@ mozInlineSpellChecker::SaveCurrentSelectionPosition()
   return NS_OK;
 }
 
-// This is a copy of nsContentUtils::ContentIsDescendantOf. Another crime
-// for XPCOM's rap sheet
-bool // static
-ContentIsDescendantOf(nsINode* aPossibleDescendant,
-                      nsINode* aPossibleAncestor)
-{
-  MOZ_ASSERT(aPossibleDescendant, "The possible descendant is null!");
-  MOZ_ASSERT(aPossibleAncestor, "The possible ancestor is null!");
-
-  do {
-    if (aPossibleDescendant == aPossibleAncestor)
-      return true;
-    aPossibleDescendant = aPossibleDescendant->GetParentNode();
-  } while (aPossibleDescendant);
-
-  return false;
-}
-
 // mozInlineSpellChecker::HandleNavigationEvent
 //
 //    Acts upon mouse clicks and keyboard navigation changes, spell checking