Bug 1827856 - Allow chrome code to properly observe UA widgets / NAC. r=smaug,devtools-reviewers,nchevobbe

Differential Revision: https://phabricator.services.mozilla.com/D175356

devtools/server/actors/inspector/node.js

@@ -271,6 +271,7 @@ class NodeActor extends Actor {
       characterDataOldValue: true,
       childList: true,
       subtree: true,
+      chromeOnlyNodes: true,
     });
     this.mutationObserver = observer;
   }

dom/base/nsDOMMutationObserver.cpp

@@ -69,8 +69,7 @@ NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(nsDOMMutationRecord, mTarget,
 // Observer
 
 bool nsMutationReceiverBase::IsObservable(nsIContent* aContent) {
-  return !aContent->ChromeOnlyAccess() &&
-         (Observer()->IsChrome() || !aContent->IsInNativeAnonymousSubtree());
+  return !aContent->ChromeOnlyAccess() || ChromeOnlyNodes();
 }
 
 bool nsMutationReceiverBase::ObservesAttr(nsINode* aRegisterTarget,
@@ -629,7 +628,7 @@ void nsDOMMutationObserver::RescheduleForRun() {
 void nsDOMMutationObserver::Observe(nsINode& aTarget,
                                     const MutationObserverInit& aOptions,
                                     nsIPrincipal& aSubjectPrincipal,
-                                    mozilla::ErrorResult& aRv) {
+                                    ErrorResult& aRv) {
   bool childList = aOptions.mChildList;
   bool attributes =
       aOptions.mAttributes.WasPassed() && aOptions.mAttributes.Value();
@@ -642,6 +641,7 @@ void nsDOMMutationObserver::Observe(nsINode& aTarget,
   bool characterDataOldValue = aOptions.mCharacterDataOldValue.WasPassed() &&
                                aOptions.mCharacterDataOldValue.Value();
   bool animations = aOptions.mAnimations;
+  bool chromeOnlyNodes = aOptions.mChromeOnlyNodes;
 
   if (!aOptions.mAttributes.WasPassed() &&
       (aOptions.mAttributeOldValue.WasPassed() ||
@@ -707,6 +707,7 @@ void nsDOMMutationObserver::Observe(nsINode& aTarget,
   r->SetAttributeFilter(std::move(filters));
   r->SetAllAttributes(allAttrs);
   r->SetAnimations(animations);
+  r->SetChromeOnlyNodes(chromeOnlyNodes);
   r->RemoveClones();
 
   if (!aSubjectPrincipal.IsSystemPrincipal() &&
@@ -793,10 +794,7 @@ already_AddRefed<nsDOMMutationObserver> nsDOMMutationObserver::Constructor(
     aRv.Throw(NS_ERROR_FAILURE);
     return nullptr;
   }
-  bool isChrome = nsContentUtils::IsChromeDoc(window->GetExtantDoc());
-  RefPtr<nsDOMMutationObserver> observer =
-      new nsDOMMutationObserver(std::move(window), aCb, isChrome);
-  return observer.forget();
+  return MakeAndAddRef<nsDOMMutationObserver>(std::move(window), aCb);
 }
 
 bool nsDOMMutationObserver::MergeableAttributeRecord(

dom/base/nsDOMMutationObserver.h

@@ -145,7 +145,7 @@ class nsMutationReceiverBase : public nsStubAnimationObserver {
     mCharacterData = aCharacterData;
   }
 
-  bool CharacterDataOldValue() {
+  bool CharacterDataOldValue() const {
     return mParent ? mParent->CharacterDataOldValue() : mCharacterDataOldValue;
   }
   void SetCharacterDataOldValue(bool aOldValue) {
@@ -153,7 +153,7 @@ class nsMutationReceiverBase : public nsStubAnimationObserver {
     mCharacterDataOldValue = aOldValue;
   }
 
-  bool NativeAnonymousChildList() {
+  bool NativeAnonymousChildList() const {
     return mParent ? mParent->NativeAnonymousChildList()
                    : mNativeAnonymousChildList;
   }
@@ -162,13 +162,15 @@ class nsMutationReceiverBase : public nsStubAnimationObserver {
     mNativeAnonymousChildList = aOldValue;
   }
 
-  bool Attributes() { return mParent ? mParent->Attributes() : mAttributes; }
+  bool Attributes() const {
+    return mParent ? mParent->Attributes() : mAttributes;
+  }
   void SetAttributes(bool aAttributes) {
     NS_ASSERTION(!mParent, "Shouldn't have parent");
     mAttributes = aAttributes;
   }
 
-  bool AllAttributes() {
+  bool AllAttributes() const {
     return mParent ? mParent->AllAttributes() : mAllAttributes;
   }
   void SetAllAttributes(bool aAll) {
@@ -176,13 +178,15 @@ class nsMutationReceiverBase : public nsStubAnimationObserver {
     mAllAttributes = aAll;
   }
 
-  bool Animations() { return mParent ? mParent->Animations() : mAnimations; }
+  bool Animations() const {
+    return mParent ? mParent->Animations() : mAnimations;
+  }
   void SetAnimations(bool aAnimations) {
     NS_ASSERTION(!mParent, "Shouldn't have parent");
     mAnimations = aAnimations;
   }
 
-  bool AttributeOldValue() {
+  bool AttributeOldValue() const {
     return mParent ? mParent->AttributeOldValue() : mAttributeOldValue;
   }
   void SetAttributeOldValue(bool aOldValue) {
@@ -190,6 +194,15 @@ class nsMutationReceiverBase : public nsStubAnimationObserver {
     mAttributeOldValue = aOldValue;
   }
 
+  bool ChromeOnlyNodes() const {
+    return mParent ? mParent->ChromeOnlyNodes() : mChromeOnlyNodes;
+  }
+
+  void SetChromeOnlyNodes(bool aChromeOnlyNodes) {
+    NS_ASSERTION(!mParent, "Shouldn't have parent");
+    mChromeOnlyNodes = aChromeOnlyNodes;
+  }
+
   nsTArray<RefPtr<nsAtom>>& AttributeFilter() { return mAttributeFilter; }
   void SetAttributeFilter(nsTArray<RefPtr<nsAtom>>&& aFilter) {
     NS_ASSERTION(!mParent, "Shouldn't have parent");
@@ -235,7 +248,8 @@ class nsMutationReceiverBase : public nsStubAnimationObserver {
         mAttributes(false),
         mAllAttributes(false),
         mAttributeOldValue(false),
-        mAnimations(false) {
+        mAnimations(false),
+        mChromeOnlyNodes(false) {
     NS_ASSERTION(mParent->Subtree(), "Should clone a non-subtree observer!");
   }
 
@@ -265,16 +279,17 @@ class nsMutationReceiverBase : public nsStubAnimationObserver {
   nsCOMPtr<nsINode> mKungFuDeathGrip;
 
  private:
-  bool mSubtree;
-  bool mChildList;
-  bool mCharacterData;
-  bool mCharacterDataOldValue;
-  bool mNativeAnonymousChildList;
-  bool mAttributes;
-  bool mAllAttributes;
-  bool mAttributeOldValue;
-  bool mAnimations;
   nsTArray<RefPtr<nsAtom>> mAttributeFilter;
+  bool mSubtree : 1;
+  bool mChildList : 1;
+  bool mCharacterData : 1;
+  bool mCharacterDataOldValue : 1;
+  bool mNativeAnonymousChildList : 1;
+  bool mAttributes : 1;
+  bool mAllAttributes : 1;
+  bool mAttributeOldValue : 1;
+  bool mAnimations : 1;
+  bool mChromeOnlyNodes : 1;
 };
 
 class nsMutationReceiver : public nsMutationReceiverBase {
@@ -412,13 +427,12 @@ class nsAnimationReceiver : public nsMutationReceiver {
 class nsDOMMutationObserver final : public nsISupports, public nsWrapperCache {
  public:
   nsDOMMutationObserver(nsCOMPtr<nsPIDOMWindowInner>&& aOwner,
-                        mozilla::dom::MutationCallback& aCb, bool aChrome)
+                        mozilla::dom::MutationCallback& aCb)
       : mOwner(std::move(aOwner)),
         mLastPendingMutation(nullptr),
         mPendingMutationCount(0),
         mCallback(&aCb),
         mWaitingForRun(false),
-        mIsChrome(aChrome),
         mMergeAttributeRecords(false),
         mId(++sCount) {}
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
@@ -426,8 +440,8 @@ class nsDOMMutationObserver final : public nsISupports, public nsWrapperCache {
   NS_DECLARE_STATIC_IID_ACCESSOR(NS_DOM_MUTATION_OBSERVER_IID)
 
   static already_AddRefed<nsDOMMutationObserver> Constructor(
-      const mozilla::dom::GlobalObject& aGlobal,
-      mozilla::dom::MutationCallback& aCb, mozilla::ErrorResult& aRv);
+      const mozilla::dom::GlobalObject&, mozilla::dom::MutationCallback&,
+      mozilla::ErrorResult&);
 
   JSObject* WrapObject(JSContext* aCx,
                        JS::Handle<JSObject*> aGivenProto) override {
@@ -436,8 +450,6 @@ class nsDOMMutationObserver final : public nsISupports, public nsWrapperCache {
 
   nsISupports* GetParentObject() const { return mOwner; }
 
-  bool IsChrome() const { return mIsChrome; }
-
   void Observe(nsINode& aTarget,
                const mozilla::dom::MutationObserverInit& aOptions,
                nsIPrincipal& aSubjectPrincipal, mozilla::ErrorResult& aRv);
@@ -561,7 +573,6 @@ class nsDOMMutationObserver final : public nsISupports, public nsWrapperCache {
   RefPtr<mozilla::dom::MutationCallback> mCallback;
 
   bool mWaitingForRun;
-  const bool mIsChrome;
   bool mMergeAttributeRecords;
 
   uint64_t mId;

dom/webidl/MutationObserver.webidl

@@ -68,6 +68,8 @@ dictionary MutationObserverInit {
   [ChromeOnly]
   boolean nativeAnonymousChildList = false;
   [ChromeOnly]
+  boolean chromeOnlyNodes = false;
+  [ChromeOnly]
   boolean animations = false;
   sequence<DOMString> attributeFilter;
 };

toolkit/content/tests/widgets/mochitest.ini

@@ -27,6 +27,7 @@ support-files =
 [test_audiocontrols_dimensions.html]
 [test_audiocontrols_fullscreen.html]
 [test_mousecapture_area.html]
+[test_nac_mutations.html]
 [test_panel_list_shadow_node_anchor.html]
 support-files =
   ../../widgets/panel-item.css

toolkit/content/tests/widgets/test_nac_mutations.html

@@ -0,0 +1,65 @@
+<!DOCTYPE HTML>
+<title>UA Widget mutation observer test</title>
+<script src="/tests/SimpleTest/SimpleTest.js"></script>
+<script src="/tests/SimpleTest/EventUtils.js"></script>
+<link rel="stylesheet" href="/tests/SimpleTest/test.css" />
+<video controls id="video"></video>
+<div style="overflow: scroll; width: 100px; height: 100px" id="scroller"></div>
+<script>
+const video = document.getElementById("video");
+const scroller = document.getElementById("scroller");
+
+async function test_mutations_internal(observedNode, elementToMutate, expectMutations) {
+  let resolveMutations;
+  let mutations = new Promise(r => {
+    resolveMutations = r;
+  });
+
+  let observer = new MutationObserver(function(m) {
+    ok(expectMutations, "Mutations should be expected");
+    resolveMutations(m)
+  });
+
+  SpecialPowers.wrap(observer).observe(observedNode, {
+    subtree: true,
+    attributes: true,
+    chromeOnlyNodes: expectMutations,
+  });
+
+  elementToMutate.setAttribute("unlikely", `value-${expectMutations}`);
+
+  if (expectMutations) {
+    await mutations;
+  } else {
+    await new Promise(r => SimpleTest.executeSoon(r));
+  }
+
+  observer.disconnect();
+}
+
+async function test_mutations(observedNode, elementToMutate) {
+  for (let chromeOnlyNodes of [true, false]) {
+    info(`Testing chromeOnlyNodes: ${chromeOnlyNodes}`);
+    await test_mutations_internal(observedNode, elementToMutate, chromeOnlyNodes);
+  }
+}
+
+add_task(async function test_ua_mutations() {
+  let shadow = SpecialPowers.wrap(video).openOrClosedShadowRoot;
+  ok(!!shadow, "UA Widget ShadowRoot exists");
+
+  await test_mutations(shadow, shadow.querySelector("*"));
+});
+
+add_task(async function test_scrollbar_mutations_same_anon_tree() {
+  let scrollbar = SpecialPowers.wrap(window).InspectorUtils.getChildrenForNode(scroller, true, false)[0];
+  is(scrollbar.tagName, "scrollbar", "should find a scrollbar");
+  await test_mutations(scrollbar, scrollbar);
+});
+
+add_task(async function test_scrollbar_mutations_same_tree() {
+  let scrollbar = SpecialPowers.wrap(window).InspectorUtils.getChildrenForNode(scroller, true, false)[0];
+  is(scrollbar.tagName, "scrollbar", "should find a scrollbar");
+  await test_mutations(scroller, scrollbar);
+});
+</script>