Bug 1403712: Make some assertions not assert for conditions that may happen mid-unbind. r=bholley

MozReview-Commit-ID: DNSphdMismy
Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>

dom/base/Element.cpp

@@ -4291,6 +4291,7 @@ BitsArePropagated(const Element* aElement, uint32_t aBits, nsINode* aRestyleRoot
     nsINode* parentNode = curr->GetParentNode();
     curr = curr->GetFlattenedTreeParentElementForStyle();
     MOZ_ASSERT_IF(!curr,
+                  !parentNode || // can only happen mid-unbind.
                   parentNode == aElement->OwnerDoc() ||
                   parentNode == parentNode->OwnerDoc()->GetRootElement());
   }
@@ -4453,7 +4454,10 @@ NoteDirtyElement(Element* aElement, uint32_t aBits)
     }
   }
 
+  // See the comment in nsIDocument::SetServoRestyleRoot about the !IsElement()
+  // check there. Same justification here.
   MOZ_ASSERT(aElement == doc->GetServoRestyleRoot() ||
+             !doc->GetServoRestyleRoot()->IsElement() ||
              nsContentUtils::ContentIsFlattenedTreeDescendantOfForStyle(
                aElement, doc->GetServoRestyleRoot()));
   MOZ_ASSERT(aElement == doc->GetServoRestyleRoot() ||

dom/base/nsIDocumentInlines.h

@@ -88,8 +88,7 @@ nsIDocument::SetServoRestyleRoot(nsINode* aRoot, uint32_t aDirtyBits)
              mServoRestyleRoot == aRoot ||
              !aRoot->IsElement() ||
              nsContentUtils::ContentIsFlattenedTreeDescendantOfForStyle(mServoRestyleRoot, aRoot));
-  MOZ_ASSERT(aRoot == aRoot->OwnerDocAsNode() ||
-             (aRoot->IsElement() && aRoot->IsInComposedDoc()));
+  MOZ_ASSERT(aRoot == aRoot->OwnerDocAsNode() || aRoot->IsElement());
   mServoRestyleRoot = aRoot;
   mServoRestyleRootDirtyBits = aDirtyBits;
 }