Use [RaisesException] for immediate promise rejections in scheduler

This is a part of effort for using [RaisesException] when synchronously
rejecting a promise.

It uses [RaisesException] for
//third_party/blink/renderer/modules/scheduler.

Bug: 1001114
Change-Id: Ic51051ce7b109e30a8995f8c5185abb6eef9d25f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1980262Reviewed-by: Nate Chapin <japhet@chromium.org>
Commit-Queue: Julie Kim <jkim@igalia.com>
Cr-Commit-Position: refs/heads/master@{#728759}

third_party/blink/renderer/modules/scheduler/dom_scheduler.cc

@@ -18,11 +18,12 @@ namespace blink {
 
 namespace {
 
-static ScriptPromise RejectPromiseImmediately(ScriptState* script_state) {
-  return ScriptPromise::RejectWithDOMException(
-      script_state,
-      MakeGarbageCollected<DOMException>(DOMExceptionCode::kNotSupportedError,
-                                         "Current document is detached"));
+static ScriptPromise RejectPromiseImmediately(ExceptionState& exception_state) {
+  // The bindings layer implicitly converts thrown exceptions in
+  // promise-returning functions to promise rejections.
+  exception_state.ThrowDOMException(DOMExceptionCode::kNotSupportedError,
+                                    "Current document is detached");
+  return ScriptPromise();
 }
 
 }  // namespace
@@ -65,9 +66,10 @@ void DOMScheduler::OnTaskCompleted(DOMTask*) {}
 ScriptPromise DOMScheduler::postTask(ScriptState* script_state,
                                      V8Function* callback_function,
                                      SchedulerPostTaskOptions* options,
-                                     const HeapVector<ScriptValue>& args) {
+                                     const HeapVector<ScriptValue>& args,
+                                     ExceptionState& exception_state) {
   if (!GetExecutionContext() || GetExecutionContext()->IsContextDestroyed())
-    return RejectPromiseImmediately(script_state);
+    return RejectPromiseImmediately(exception_state);
 
   // Always honor the priority and the task signal if given. Therefore:
   // * If both priority and signal are set, use the signal but choose the
@@ -89,7 +91,7 @@ ScriptPromise DOMScheduler::postTask(ScriptState* script_state,
   } else if (auto* task_signal = DynamicTo<DOMTaskSignal>(options->signal())) {
     task_runner = task_signal->GetTaskRunner();
     if (!task_runner)
-      return RejectPromiseImmediately(script_state);
+      return RejectPromiseImmediately(exception_state);
   } else {
     task_runner = GetTaskRunnerFor(WebSchedulingPriority::kDefaultPriority);
   }

third_party/blink/renderer/modules/scheduler/dom_scheduler.h

@@ -18,6 +18,7 @@
 namespace blink {
 
 class DOMTask;
+class ExceptionState;
 class ExecutionContext;
 class SchedulerPostTaskOptions;
 class ScriptValue;
@@ -46,7 +47,8 @@ class MODULES_EXPORT DOMScheduler : public ScriptWrappable,
   ScriptPromise postTask(ScriptState*,
                          V8Function*,
                          SchedulerPostTaskOptions*,
-                         const HeapVector<ScriptValue>& args);
+                         const HeapVector<ScriptValue>& args,
+                         ExceptionState&);
 
   // Callbacks invoked by DOMTasks when they run.
   void OnTaskStarted(DOMTask*);

third_party/blink/renderer/modules/scheduler/scheduler.idl

@@ -8,5 +8,5 @@
     ImplementedAs=DOMScheduler,
     RuntimeEnabled=WebScheduler
 ] interface Scheduler {
-    [CallWith=ScriptState] Promise<any> postTask(Function callback, optional SchedulerPostTaskOptions options, any... arguments);
+    [CallWith=ScriptState, RaisesException] Promise<any> postTask(Function callback, optional SchedulerPostTaskOptions options, any... arguments);
 };