1. diff --git a/accessible/ipc/DocAccessibleParent.cpp b/accessible/ipc/DocAccessibleParent.cpp
  2. index a847c36..61e3db8 100644
  3. --- a/accessible/ipc/DocAccessibleParent.cpp
  4. +++ b/accessible/ipc/DocAccessibleParent.cpp
  5. @@ -266,14 +266,14 @@ DocAccessibleParent::Destroy()
  6. }
  8. bool
  9. -DocAccessibleParent::CheckDocTree() const
  10. +DocAccessibleParent::CheckDocTreeInternal() const
  11. {
  12. size_t childDocs = mChildDocs.Length();
  13. for (size_t i = 0; i < childDocs; i++) {
  14. if (!mChildDocs[i] || mChildDocs[i]->mParentDoc != this)
  15. return false;
  17. - if (!mChildDocs[i]->CheckDocTree()) {
  18. + if (!mChildDocs[i]->CheckDocTreeInternal()) {
  19. return false;
  20. }
  21. }
  22. @@ -281,5 +281,19 @@ DocAccessibleParent::CheckDocTree() const
  23. return true;
  24. }
  26. +bool
  27. +DocAccessibleParent::CheckDocTree() const
  28. +{
  29. + const DocAccessibleParent* doc = this;
  30. + while (doc->ParentDoc()) {
  31. + doc = doc->ParentDoc();
  32. + }
  33. +
  34. + if (!doc->mTopLevel) {
  35. + return false;
  36. + }
  37. +
  38. + return doc->CheckDocTreeInternal();
  39. +}
  40. } // a11y
  41. } // mozilla
  42. diff --git a/accessible/ipc/DocAccessibleParent.h b/accessible/ipc/DocAccessibleParent.h
  43. index f9e6cc5..0b80d4d 100644
  44. --- a/accessible/ipc/DocAccessibleParent.h
  45. +++ b/accessible/ipc/DocAccessibleParent.h
  46. @@ -72,8 +72,10 @@ public:
  47. void Destroy();
  48. virtual void ActorDestroy(ActorDestroyReason aWhy) override
  49. {
  50. + if (mShutdown)
  51. + return;
  52. +
  53. MOZ_DIAGNOSTIC_ASSERT(CheckDocTree());
  54. - if (!mShutdown)
  55. Destroy();
  56. }
  58. @@ -152,6 +154,7 @@ private:
  59. const nsTArray<AccessibleData>& aNewTree, uint32_t aIdx,
  60. uint32_t aIdxInParent);
  61. MOZ_WARN_UNUSED_RESULT bool CheckDocTree() const;
  62. + MOZ_WARN_UNUSED_RESULT bool CheckDocTreeInternal() const;
  64. nsTArray<DocAccessibleParent*> mChildDocs;
  65. DocAccessibleParent* mParentDoc;