Bug 1487312 - Fix content insertion accessibility notifications in Shadow DOM. r=Jamie,surkov

The issue was specific to content insertion directly under a shadow root, the
rest should work (see bug 1427825 for the fix for other similar occurrences).

The removal of the aContainer argument follows the same pattern as bug 1442207.

Differential Revision: https://phabricator.services.mozilla.com/D6431

accessible/base/NotificationController.cpp

@@ -417,27 +417,39 @@ NotificationController::ScheduleChildDocBinding(DocAccessible* aDocument)
 }
 
 void
-NotificationController::ScheduleContentInsertion(Accessible* aContainer,
-                                                 nsIContent* aStartChildNode,
+NotificationController::ScheduleContentInsertion(nsIContent* aStartChildNode,
                                                  nsIContent* aEndChildNode)
 {
-  nsTArray<nsCOMPtr<nsIContent>> list;
+  // The frame constructor guarantees that only ranges with the same parent
+  // arrive here in presence of dynamic changes to the page, see
+  // nsCSSFrameConstructor::IssueSingleInsertNotifications' callers.
+  nsINode* parent = aStartChildNode->GetFlattenedTreeParentNode();
+  if (!parent) {
+    return;
+  }
 
-  bool needsProcessing = false;
-  nsIContent* node = aStartChildNode;
-  while (node != aEndChildNode) {
+  Accessible* container = mDocument->AccessibleOrTrueContainer(parent);
+  if (!container) {
+    return;
+  }
+
+  AutoTArray<nsCOMPtr<nsIContent>, 10> list;
+  for (nsIContent* node = aStartChildNode;
+       node != aEndChildNode;
+       node = node->GetNextSibling()) {
+    MOZ_ASSERT(parent == node->GetFlattenedTreeParentNode());
     // Notification triggers for content insertion even if no content was
     // actually inserted, check if the given content has a frame to discard
     // this case early.
+    //
+    // TODO(emilio): Should this handle display: contents?
     if (node->GetPrimaryFrame()) {
-      if (list.AppendElement(node))
-        needsProcessing = true;
+      list.AppendElement(node);
     }
-    node = node->GetNextSibling();
   }
 
-  if (needsProcessing) {
-    mContentInsertions.LookupOrAdd(aContainer)->AppendElements(list);
+  if (!list.IsEmpty()) {
+    mContentInsertions.LookupOrAdd(container)->AppendElements(list);
     ScheduleProcessing();
   }
 }

accessible/base/NotificationController.h

@@ -195,8 +195,7 @@ public:
   /**
    * Pend accessible tree update for content insertion.
    */
-  void ScheduleContentInsertion(Accessible* aContainer,
-                                nsIContent* aStartChildNode,
+  void ScheduleContentInsertion(nsIContent* aStartChildNode,
                                 nsIContent* aEndChildNode);
 
   /**

accessible/base/nsAccessibilityService.cpp

@@ -385,10 +385,7 @@ nsAccessibilityService::ListenersChanged(nsIArray* aEventChanges)
       // handler.
       if (document && !document->HasAccessible(node) &&
           nsCoreUtils::HasClickListener(node)) {
-        nsIContent* parentEl = node->GetFlattenedTreeParent();
-        if (parentEl) {
-          document->ContentInserted(parentEl, node, node->GetNextSibling());
-        }
+        document->ContentInserted(node, node->GetNextSibling());
         break;
       }
     }
@@ -611,7 +608,7 @@ nsAccessibilityService::DeckPanelSwitched(nsIPresShell* aPresShell,
     }
 #endif
 
-    document->ContentInserted(aDeckNode, panelNode, panelNode->GetNextSibling());
+    document->ContentInserted(panelNode, panelNode->GetNextSibling());
   }
 }
 
@@ -635,7 +632,7 @@ nsAccessibilityService::ContentRangeInserted(nsIPresShell* aPresShell,
 #endif
 
   if (document) {
-    document->ContentInserted(aStartChild->GetParent(), aStartChild, aEndChild);
+    document->ContentInserted(aStartChild, aEndChild);
   }
 }
 

accessible/generic/DocAccessible.cpp

@@ -777,10 +777,8 @@ DocAccessible::AttributeChanged(dom::Element* aElement,
   if (aAttribute == nsGkAtoms::aria_hidden) {
     if (aria::HasDefinedARIAHidden(aElement)) {
       ContentRemoved(aElement);
-    }
-    else {
-      ContentInserted(aElement->GetFlattenedTreeParent(),
-                      aElement, aElement->GetNextSibling());
+    } else {
+      ContentInserted(aElement, aElement->GetNextSibling());
     }
     return;
   }
@@ -1353,8 +1351,7 @@ DocAccessible::UnbindFromDocument(Accessible* aAccessible)
 }
 
 void
-DocAccessible::ContentInserted(nsIContent* aContainerNode,
-                               nsIContent* aStartChildNode,
+DocAccessible::ContentInserted(nsIContent* aStartChildNode,
                                nsIContent* aEndChildNode)
 {
   // Ignore content insertions until we constructed accessible tree. Otherwise
@@ -1362,14 +1359,8 @@ DocAccessible::ContentInserted(nsIContent* aContainerNode,
   if (mNotificationController && HasLoadState(eTreeConstructed)) {
     // Update the whole tree of this document accessible when the container is
     // null (document element is inserted or removed).
-    Accessible* container = aContainerNode ?
-      AccessibleOrTrueContainer(aContainerNode) : this;
-    if (container) {
-      // Ignore notification if the container node is no longer in the DOM tree.
-      mNotificationController->ScheduleContentInsertion(container,
-                                                        aStartChildNode,
-                                                        aEndChildNode);
-    }
+    mNotificationController->ScheduleContentInsertion(aStartChildNode,
+                                                      aEndChildNode);
   }
 }
 
@@ -1388,10 +1379,8 @@ DocAccessible::RecreateAccessible(nsIContent* aContent)
   // subclass hide and show events to handle them separately and implement their
   // coalescence with normal hide and show events. Note, in this case they
   // should be coalesced with normal show/hide events.
-
-  nsIContent* parent = aContent->GetFlattenedTreeParent();
   ContentRemoved(aContent);
-  ContentInserted(parent, aContent, aContent->GetNextSibling());
+  ContentInserted(aContent, aContent->GetNextSibling());
 }
 
 void

accessible/generic/DocAccessible.h

@@ -350,9 +350,7 @@ public:
   /**
    * Notify the document accessible that content was inserted.
    */
-  void ContentInserted(nsIContent* aContainerNode,
-                       nsIContent* aStartChildNode,
-                       nsIContent* aEndChildNode);
+  void ContentInserted(nsIContent* aStartChildNode, nsIContent* aEndChildNode);
 
   /**
    * Update the tree on content removal.

accessible/tests/mochitest/treeupdate/test_bug1276857.html

@@ -81,13 +81,17 @@
 
         var shadowRoot = iframe.contentDocument.getElementById("c2_c").shadowRoot;
         shadowRoot.firstElementChild.querySelector("span").remove();
+        // bug 1487312
+        shadowRoot.firstElementChild.offsetTop;
+        shadowRoot.appendChild(document.createElement("button"));
       };
 
       this.finalCheck = function runShadowTest_finalCheck() {
         var tree = {
           SECTION: [ // c2
             { TEXT_LEAF: [] }, // Some text
-            { TEXT_LEAF: [] } // More text
+            { TEXT_LEAF: [] }, // More text
+            { PUSHBUTTON: [] } // The button we appended.
           ]
         };
         testAccessibleTree(iframe.contentDocument.getElementById("c2"), tree);