Bug 1115812 patch 14 - For rem unit change handling, repost min hint to root just like change hint. r=heycam

This changes what was probably a silly design choice when I wrote the
code for 'rem'-basis handling; we shouldn't try continuing through the
rest of RestyleElement() here, but instead repost the hint to the
rebuild-all process.

layout/base/RestyleManager.cpp

@@ -951,11 +951,9 @@ RestyleManager::RestyleElement(Element*        aElement,
         // The basis for 'rem' units has changed.
         newContext = nullptr;
         mRebuildAllRestyleHint |= aRestyleHint;
+        NS_UpdateHint(mRebuildAllExtraHint, aMinHint);
         DoRebuildAllStyleData(aRestyleTracker);
-        if (aMinHint == 0) {
-          return;
-        }
-        aPrimaryFrame = aElement->GetPrimaryFrame();
+        return;
       }
     }
   }