Bug 1363595: Invalidate accessible handler cache when change events occur; r=eeejay

MozReview-Commit-ID: kODsDsy9vJ

--HG--
extra : rebase_source : 653d7fa5694eb767df974f8b1df92cdf8d77c662

accessible/windows/msaa/AccessibleWrap.cpp

@@ -1137,6 +1137,35 @@ AccessibleWrap::SetID(uint32_t aID)
   mID = aID;
 }
 
+static bool
+IsHandlerInvalidationNeeded(uint32_t aEvent)
+{
+  // We want to return true for any events that would indicate that something
+  // in the handler cache is out of date.
+  switch (aEvent) {
+    case EVENT_OBJECT_STATECHANGE:
+    case EVENT_OBJECT_LOCATIONCHANGE:
+    case EVENT_OBJECT_NAMECHANGE:
+    case EVENT_OBJECT_DESCRIPTIONCHANGE:
+    case EVENT_OBJECT_VALUECHANGE:
+    case IA2_EVENT_ACTION_CHANGED:
+    case IA2_EVENT_DOCUMENT_LOAD_COMPLETE:
+    case IA2_EVENT_DOCUMENT_LOAD_STOPPED:
+    case IA2_EVENT_DOCUMENT_ATTRIBUTE_CHANGED:
+    case IA2_EVENT_DOCUMENT_CONTENT_CHANGED:
+    case IA2_EVENT_PAGE_CHANGED:
+    case IA2_EVENT_TEXT_ATTRIBUTE_CHANGED:
+    case IA2_EVENT_TEXT_CHANGED:
+    case IA2_EVENT_TEXT_INSERTED:
+    case IA2_EVENT_TEXT_REMOVED:
+    case IA2_EVENT_TEXT_UPDATED:
+    case IA2_EVENT_OBJECT_ATTRIBUTE_CHANGED:
+      return true;
+    default:
+      return false;
+  }
+}
+
 void
 AccessibleWrap::FireWinEvent(Accessible* aTarget, uint32_t aEventType)
 {
@@ -1159,6 +1188,10 @@ AccessibleWrap::FireWinEvent(Accessible* aTarget, uint32_t aEventType)
     return;
   }
 
+  if (IsHandlerInvalidationNeeded(winEvent)) {
+    InvalidateHandlers();
+  }
+
   // Fire MSAA event for client area window.
   ::NotifyWinEvent(winEvent, hwnd, OBJID_CLIENT, childID);