Bug 1791761 - Add support for nsISerialEventTarget and nsIDirectTaskDispatcher to RemoteLazyInputStreamThread; r=dom-storage-reviewers,jesup

Differential Revision: https://phabricator.services.mozilla.com/D157818

dom/file/ipc/RemoteLazyInputStreamThread.cpp

@@ -47,7 +47,8 @@ class ThreadInitializeRunnable final : public Runnable {
 
 }  // namespace
 
-NS_IMPL_ISUPPORTS(RemoteLazyInputStreamThread, nsIObserver, nsIEventTarget)
+NS_IMPL_ISUPPORTS(RemoteLazyInputStreamThread, nsIObserver, nsIEventTarget,
+                  nsISerialEventTarget, nsIDirectTaskDispatcher)
 
 bool RLISThreadIsInOrBeyondShutdown() {
   // ShutdownPhase::XPCOMShutdownThreads matches
@@ -182,6 +183,46 @@ RemoteLazyInputStreamThread::UnregisterShutdownTask(nsITargetShutdownTask*) {
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
+NS_IMETHODIMP
+RemoteLazyInputStreamThread::DispatchDirectTask(
+    already_AddRefed<nsIRunnable> aRunnable) {
+  nsCOMPtr<nsIRunnable> runnable(aRunnable);
+
+  StaticMutexAutoLock lock(gRemoteLazyThreadMutex);
+
+  nsCOMPtr<nsIDirectTaskDispatcher> dispatcher = do_QueryInterface(mThread);
+
+  if (dispatcher) {
+    return dispatcher->DispatchDirectTask(runnable.forget());
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP RemoteLazyInputStreamThread::DrainDirectTasks() {
+  StaticMutexAutoLock lock(gRemoteLazyThreadMutex);
+
+  nsCOMPtr<nsIDirectTaskDispatcher> dispatcher = do_QueryInterface(mThread);
+
+  if (dispatcher) {
+    return dispatcher->DrainDirectTasks();
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP RemoteLazyInputStreamThread::HaveDirectTasks(bool* aValue) {
+  StaticMutexAutoLock lock(gRemoteLazyThreadMutex);
+
+  nsCOMPtr<nsIDirectTaskDispatcher> dispatcher = do_QueryInterface(mThread);
+
+  if (dispatcher) {
+    return dispatcher->HaveDirectTasks(aValue);
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
 bool IsOnDOMFileThread() {
   MOZ_ASSERT(!RLISThreadIsInOrBeyondShutdown());
 

dom/file/ipc/RemoteLazyInputStreamThread.h

@@ -18,12 +18,16 @@ namespace mozilla {
 
 class RemoteLazyInputStreamChild;
 
+// XXX Rename this class since it's used by LSNG too.
 class RemoteLazyInputStreamThread final : public nsIObserver,
-                                          public nsIEventTarget {
+                                          public nsISerialEventTarget,
+                                          public nsIDirectTaskDispatcher {
  public:
   NS_DECL_THREADSAFE_ISUPPORTS
   NS_DECL_NSIOBSERVER
   NS_DECL_NSIEVENTTARGET
+  NS_DECL_NSISERIALEVENTTARGET
+  NS_DECL_NSIDIRECTTASKDISPATCHER
 
   static RemoteLazyInputStreamThread* Get();