Bug 1123523 - Part 5: Record on a document whether it might have any nsIAnimationObservers registered. r=smaug

dom/base/nsIDocument.h

@@ -2198,6 +2198,16 @@ public:
     mMayHaveDOMMutationObservers = true;
   }
 
+  bool MayHaveAnimationObservers()
+  {
+    return mMayHaveAnimationObservers;
+  }
+
+  void SetMayHaveAnimationObservers()
+  {
+    mMayHaveAnimationObservers = true;
+  }
+
   bool IsInSyncOperation()
   {
     return mInSyncOperationCount != 0;
@@ -2694,6 +2704,9 @@ protected:
   // True if a DOMMutationObserver is perhaps attached to a node in the document.
   bool mMayHaveDOMMutationObservers;
 
+  // True if an nsIAnimationObserver is perhaps attached to a node in the document.
+  bool mMayHaveAnimationObservers;
+
   // True if a document has loaded Mixed Active Script (see nsMixedContentBlocker.cpp)
   bool mHasMixedActiveContentLoaded;
 

dom/base/nsINode.cpp

@@ -104,6 +104,7 @@
 #include "nsGlobalWindow.h"
 #include "nsDOMMutationObserver.h"
 #include "GeometryUtils.h"
+#include "nsIAnimationObserver.h"
 
 using namespace mozilla;
 using namespace mozilla::dom;
@@ -2748,3 +2749,18 @@ nsINode::GetScopeChainParent() const
 {
   return nullptr;
 }
+
+void
+nsINode::AddAnimationObserver(nsIAnimationObserver* aAnimationObserver)
+{
+  AddMutationObserver(aAnimationObserver);
+  OwnerDoc()->SetMayHaveAnimationObservers();
+}
+
+void
+nsINode::AddAnimationObserverUnlessExists(
+                               nsIAnimationObserver* aAnimationObserver)
+{
+  AddMutationObserverUnlessExists(aAnimationObserver);
+  OwnerDoc()->SetMayHaveAnimationObservers();
+}

dom/base/nsINode.h

@@ -33,6 +33,7 @@ class nsAttrAndChildArray;
 class nsChildContentList;
 struct nsCSSSelectorList;
 class nsDOMAttributeMap;
+class nsIAnimationObserver;
 class nsIContent;
 class nsIDocument;
 class nsIDOMElement;
@@ -948,6 +949,9 @@ public:
    * adding observers while inside a notification is not a good idea.  An
    * observer that is already observing the node must not be added without
    * being removed first.
+   *
+   * For mutation observers that implement nsIAnimationObserver, use
+   * AddAnimationObserver instead.
    */
   void AddMutationObserver(nsIMutationObserver* aMutationObserver)
   {
@@ -961,6 +965,9 @@ public:
   /**
    * Same as above, but only adds the observer if its not observing
    * the node already.
+   *
+   * For mutation observers that implement nsIAnimationObserver, use
+   * AddAnimationObserverUnlessExists instead.
    */
   void AddMutationObserverUnlessExists(nsIMutationObserver* aMutationObserver)
   {
@@ -968,6 +975,20 @@ public:
     s->mMutationObservers.AppendElementUnlessExists(aMutationObserver);
   }
 
+  /**
+   * Same as AddMutationObserver, but for nsIAnimationObservers.  This
+   * additionally records on the document that animation observers have
+   * been registered, which is used to determine whether notifications
+   * must be fired when animations are added, removed or changed.
+   */
+  void AddAnimationObserver(nsIAnimationObserver* aAnimationObserver);
+
+  /**
+   * Same as above, but only adds the observer if its not observing
+   * the node already.
+   */
+  void AddAnimationObserverUnlessExists(nsIAnimationObserver* aAnimationObserver);
+
   /**
    * Removes a mutation observer.
    */

dom/base/nsNodeUtils.cpp

@@ -457,6 +457,10 @@ nsNodeUtils::CloneAndAdopt(nsINode *aNode, bool aClone, bool aDeep,
       newDoc->SetMayHaveDOMMutationObservers();
     }
 
+    if (oldDoc != newDoc && oldDoc->MayHaveAnimationObservers()) {
+      newDoc->SetMayHaveAnimationObservers();
+    }
+
     if (elem) {
       elem->RecompileScriptEventListeners();
     }