Bug 1882344 - Have Document instead of WakeLockJS release locks on loss of activity. r=edgar,dom-core

Differential Revision: https://phabricator.services.mozilla.com/D202853

dom/base/Document.cpp

@@ -7683,6 +7683,10 @@ static void NotifyActivityChangedCallback(nsISupports* aSupports) {
 
 void Document::NotifyActivityChanged() {
   EnumerateActivityObservers(NotifyActivityChangedCallback);
+  // https://w3c.github.io/screen-wake-lock/#handling-document-loss-of-full-activity
+  if (!IsActive()) {
+    UnlockAllWakeLocks(WakeLockType::Screen);
+  }
 }
 
 void Document::SetContainer(nsDocShell* aContainer) {
@@ -15690,6 +15694,11 @@ void Document::UpdateVisibilityState(DispatchVisibilityChange aDispatchEvent) {
     for (auto* listener : mWorkerListeners) {
       listener->OnVisible(visible);
     }
+
+    // https://w3c.github.io/screen-wake-lock/#handling-document-loss-of-visibility
+    if (!visible) {
+      UnlockAllWakeLocks(WakeLockType::Screen);
+    }
   }
 }
 
@@ -18339,9 +18348,13 @@ class UnlockAllWakeLockRunnable final : public Runnable {
 
 void Document::UnlockAllWakeLocks(WakeLockType aType) {
   // Perform unlock in a runnable to prevent UnlockAll being MOZ_CAN_RUN_SCRIPT
-  RefPtr<UnlockAllWakeLockRunnable> runnable =
-      MakeRefPtr<UnlockAllWakeLockRunnable>(aType, this);
-  NS_DispatchToMainThread(runnable);
+  if (!ActiveWakeLocks(aType).IsEmpty()) {
+    RefPtr<UnlockAllWakeLockRunnable> runnable =
+        MakeRefPtr<UnlockAllWakeLockRunnable>(aType, this);
+    nsresult rv = NS_DispatchToMainThread(runnable);
+    MOZ_DIAGNOSTIC_ASSERT(NS_SUCCEEDED(rv));
+    Unused << rv;
+  }
 }
 
 RefPtr<Document::AutomaticStorageAccessPermissionGrantPromise>

dom/power/WakeLockJS.cpp

@@ -127,8 +127,7 @@ NS_IMPL_CYCLE_COLLECTING_RELEASE(WakeLockJS)
 
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(WakeLockJS)
   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
-  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDOMEventListener)
-  NS_INTERFACE_MAP_ENTRY(nsIDocumentActivity)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIObserver)
   NS_INTERFACE_MAP_ENTRY(nsIObserver)
   NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
 NS_INTERFACE_MAP_END
@@ -148,14 +147,12 @@ JSObject* WakeLockJS::WrapObject(JSContext* aCx,
 
 // https://w3c.github.io/screen-wake-lock/#the-request-method Step 7.3
 Result<already_AddRefed<WakeLockSentinel>, WakeLockJS::RequestError>
-WakeLockJS::Obtain(WakeLockType aType) {
+WakeLockJS::Obtain(WakeLockType aType, Document* aDoc) {
   // Step 7.3.1. check visibility again
-  nsCOMPtr<Document> doc = mWindow->GetExtantDoc();
-  if (!doc) {
-    return Err(RequestError::InternalFailure);
-  }
-  if (doc->Hidden()) {
-    return Err(RequestError::DocHidden);
+  // Out of spec, but also check everything else
+  RequestError rv = WakeLockAllowedForDocument(aDoc);
+  if (rv != RequestError::Success) {
+    return Err(rv);
   }
   // Step 7.3.3. let lock be a new WakeLockSentinel
   RefPtr<WakeLockSentinel> lock =
@@ -166,7 +163,7 @@ WakeLockJS::Obtain(WakeLockType aType) {
   }
 
   // Steps 7.3.4. append lock to locks
-  doc->ActiveWakeLocks(aType).Insert(lock);
+  aDoc->ActiveWakeLocks(aType).Insert(lock);
 
   return lock.forget();
 }
@@ -191,8 +188,9 @@ already_AddRefed<Promise> WakeLockJS::Request(WakeLockType aType,
   // For now, we don't check the permission as we always grant the lock
   // Step 7.3. Queue a task
   NS_DispatchToMainThread(NS_NewRunnableFunction(
-      "ObtainWakeLock", [aType, promise, self = RefPtr<WakeLockJS>(this)]() {
-        auto lockOrErr = self->Obtain(aType);
+      "ObtainWakeLock",
+      [aType, promise, doc, self = RefPtr<WakeLockJS>(this)]() {
+        auto lockOrErr = self->Obtain(aType, doc);
         if (lockOrErr.isOk()) {
           RefPtr<WakeLockSentinel> lock = lockOrErr.unwrap();
           promise->MaybeResolve(lock);
@@ -208,30 +206,16 @@ already_AddRefed<Promise> WakeLockJS::Request(WakeLockType aType,
 }
 
 void WakeLockJS::AttachListeners() {
-  nsCOMPtr<Document> doc = mWindow->GetExtantDoc();
-  MOZ_ASSERT(doc);
-  DebugOnly<nsresult> rv =
-      doc->AddSystemEventListener(u"visibilitychange"_ns, this, true, false);
-  MOZ_ASSERT(NS_SUCCEEDED(rv));
-  doc->RegisterActivityObserver(ToSupports(this));
-
   hal::RegisterBatteryObserver(this);
 
   nsCOMPtr<nsIPrefBranch> prefBranch = do_GetService(NS_PREFSERVICE_CONTRACTID);
   MOZ_ASSERT(prefBranch);
-  rv = prefBranch->AddObserver("dom.screenwakelock.enabled", this, true);
+  DebugOnly<nsresult> rv =
+      prefBranch->AddObserver("dom.screenwakelock.enabled", this, true);
   MOZ_ASSERT(NS_SUCCEEDED(rv));
 }
 
 void WakeLockJS::DetachListeners() {
-  if (mWindow) {
-    if (nsCOMPtr<Document> doc = mWindow->GetExtantDoc()) {
-      doc->RemoveSystemEventListener(u"visibilitychange"_ns, this, true);
-
-      doc->UnregisterActivityObserver(ToSupports(this));
-    }
-  }
-
   hal::UnregisterBatteryObserver(this);
 
   if (nsCOMPtr<nsIPrefBranch> prefBranch =
@@ -252,30 +236,6 @@ NS_IMETHODIMP WakeLockJS::Observe(nsISupports* aSubject, const char* aTopic,
   return NS_OK;
 }
 
-void WakeLockJS::NotifyOwnerDocumentActivityChanged() {
-  nsCOMPtr<Document> doc = mWindow->GetExtantDoc();
-  MOZ_ASSERT(doc);
-  if (!doc->IsActive()) {
-    doc->UnlockAllWakeLocks(WakeLockType::Screen);
-  }
-}
-
-NS_IMETHODIMP WakeLockJS::HandleEvent(Event* aEvent) {
-  nsAutoString type;
-  aEvent->GetType(type);
-
-  if (type.EqualsLiteral("visibilitychange")) {
-    nsCOMPtr<Document> doc = do_QueryInterface(aEvent->GetTarget());
-    NS_ENSURE_STATE(doc);
-
-    if (doc->Hidden()) {
-      doc->UnlockAllWakeLocks(WakeLockType::Screen);
-    }
-  }
-
-  return NS_OK;
-}
-
 void WakeLockJS::Notify(const hal::BatteryInformation& aBatteryInfo) {
   if (aBatteryInfo.level() > MIN_BATTERY_LEVEL || aBatteryInfo.charging()) {
     return;

dom/power/WakeLockJS.h

@@ -39,20 +39,15 @@ namespace mozilla::dom {
  *
  * https://www.w3.org/TR/screen-wake-lock/#the-wakelock-interface
  */
-class WakeLockJS final : public nsIDOMEventListener,
+class WakeLockJS final : public nsIObserver,
                          public nsWrapperCache,
                          public hal::BatteryObserver,
-                         public nsIDocumentActivity,
-                         public nsIObserver,
                          public nsSupportsWeakReference {
  public:
-  NS_DECL_NSIDOMEVENTLISTENER
-  NS_DECL_NSIDOCUMENTACTIVITY
   NS_DECL_NSIOBSERVER
 
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
-  NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS_AMBIGUOUS(WakeLockJS,
-                                                        nsIDOMEventListener)
+  NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS_AMBIGUOUS(WakeLockJS, nsIObserver)
 
  public:
   explicit WakeLockJS(nsPIDOMWindowInner* aWindow);
@@ -89,7 +84,7 @@ class WakeLockJS final : public nsIDOMEventListener,
   void DetachListeners();
 
   Result<already_AddRefed<WakeLockSentinel>, RequestError> Obtain(
-      WakeLockType aType);
+      WakeLockType aType, Document* aDoc);
 
   RefPtr<nsPIDOMWindowInner> mWindow;
 };

dom/power/tests/file_empty.html

@@ -0,0 +1 @@
+<h1>Example page</h1>

dom/power/tests/mochitest.toml

@@ -1,9 +1,14 @@
 [DEFAULT]
 prefs = ["dom.screenwakelock.enabled=true"]
 scheme = "https"
+support-files = [
+  "file_empty.html",
+]
 
 ["test_dynamic_pref_change.html"]
 fail-if = ["xorigin"]  # cross-origin use requires permissions policy
 
 ["test_wakelock_default_permission.html"]
 fail-if = ["xorigin"]  # cross-origin use requires permissions policy
+
+["test_wakelock_on_initial_about_blank.html"]

dom/power/tests/test_wakelock_on_initial_about_blank.html

@@ -0,0 +1,49 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test requesting lock on the initial about:blank</title>
+  <link rel="help" href="https://bugzilla.mozilla.org/1882344"/>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" href="/tests/SimpleTest/test.css"/>
+  <script>
+
+    add_task(async function test() {
+      const iframe = document.createElement('iframe');
+      iframe.src = "file_empty.html";
+      document.documentElement.appendChild(iframe);
+
+      // https://html.spec.whatwg.org/multipage/nav-history-apis.html#the-window-object:initialise-the-document-object
+      is(iframe.contentWindow.location.href, "about:blank", "Initial about:blank is loaded");
+
+      let lock;
+      try {
+        // request lock on initial about:blank
+        lock = await iframe.contentWindow.navigator.wakeLock.request();
+      } catch (err) {
+        // This could happen if the initial about:blank document is inactive
+        // once the async code in .request runs.
+        ok(true, "request was rejected");
+        return;
+      }
+
+      if (iframe.contentWindow.location.href == "about:blank") {
+        await new Promise((res, _rej) => { iframe.onload = res; });
+      }
+      isnot(iframe.contentWindow.location.href, "about:blank", "Target document is loaded");
+
+      is(lock.released, true, "lock was released by load of target doc");
+
+      // window and wakeLock object stayed the same, but document changed
+      await iframe.contentWindow.navigator.wakeLock.request();
+      ok(true, "Was able to request lock on target document");
+    });
+
+  </script>
+</head>
+<body>
+<p id="display"></p>
+<div id="content" style="display: none"></div>
+<pre id="test"></pre>
+</body>
+</html>