Bug 1490974 Part 2: Remove an assert that insists only editable elements can use independent selection. r=mikedeboer

Depends on D10631

Differential Revision: https://phabricator.services.mozilla.com/D21428

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

toolkit/components/typeaheadfind/nsTypeAheadFind.cpp

@@ -586,14 +586,10 @@ nsresult nsTypeAheadFind::FindItNow(nsIPresShell* aPresShell, bool aIsLinksOnly,
         }
 
         // If we reach here without setting mFoundEditable, then something
-        // besides editable elements can cause us to have an independent
-        // selection controller.  I don't know whether this is possible.
-        // Currently, we simply fall back to grabbing the document's selection
-        // controller in this case.  Perhaps we should reject this find match
-        // and search again.
-        NS_ASSERTION(mFoundEditable,
-                     "Independent selection controller on "
-                     "non-editable element!");
+        // besides editable elements gave us an independent selection
+        // controller. List controls with multiple visible elements can do
+        // this (nsAreaSelectsFrame), and possibly others. We fall back to
+        // grabbing the document's selection controller in this case.
       }
 
       if (!mFoundEditable) {