Bug 389851. Accessible value not working with ARIA progressbars and sliders. r=scott@bashautomation.com, a=dsicore

accessible/src/base/nsAccessible.cpp

@@ -211,6 +211,7 @@ nsresult nsAccessible::QueryInterface(REFNSIID aIID, void** aInstancePtr)
           nsIContent::ATTR_VALUE_NO_MATCH) {
         *aInstancePtr = static_cast<nsIAccessibleSelectable*>(this);
         NS_ADDREF_THIS();
+        return NS_OK;
       }
     }
   }
@@ -219,6 +220,7 @@ nsresult nsAccessible::QueryInterface(REFNSIID aIID, void** aInstancePtr)
     if (mRoleMapEntry && mRoleMapEntry->valueRule != eNoValue) {
       *aInstancePtr = static_cast<nsIAccessibleValue*>(this);
       NS_ADDREF_THIS();
+      return NS_OK;
     }
   }                       
 

accessible/src/base/nsDocAccessible.cpp

@@ -1770,6 +1770,18 @@ NS_IMETHODIMP nsDocAccessible::InvalidateCacheSubtree(nsIContent *aChild,
     }
   }
 
+  if (!isShowing) {
+    // Fire an event so the assistive technology knows the children have changed
+    // This is only used by older MSAA clients. Newer ones should derive this
+    // from SHOW and HIDE so that they don't fetch extra objects
+    if (childAccessible) {
+      nsCOMPtr<nsIAccessibleEvent> reorderEvent =
+        new nsAccEvent(nsIAccessibleEvent::EVENT_REORDER, containerAccessible, nsnull, PR_TRUE);
+      NS_ENSURE_TRUE(reorderEvent, NS_ERROR_OUT_OF_MEMORY);
+      FireDelayedAccessibleEvent(reorderEvent, eCoalesceFromSameSubtree, isAsynch);
+    }
+  }
+
   return NS_OK;
 }