Use nullable interface for RequestInit AbortSignal

R=kinuko@chromium.org, peria@chromium.org, ricea@chromium.org, yhirano@chromium.org, yoav@yoav.ws

Bug: 855968
Change-Id: I96be3b769dd75300553f639ca5fa8158771bde2c
Reviewed-on: https://chromium-review.googlesource.com/1137930
Commit-Queue: Dominic Farolino <domfarolino@gmail.com>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Yoav Weiss <yoav@yoav.ws>
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Reviewed-by: Adam Rice <ricea@chromium.org>
Reviewed-by: Yutaka Hirano <yhirano@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576204}

third_party/WebKit/LayoutTests/http/tests/fetch/script-tests/request.js

@@ -746,17 +746,22 @@ test(() => {
 
 
 test(() => {
-  // At the time of writing this test, an `any` type is used to represent
-  // RequestInit's signal member instead of AbortSignal due to a bug in the IDL
-  // compiler; see https://crbug.com/855968. This test ensures that that we
-  // treat the `any` member exactly as an AbortSignal member would be treated.
+  // This is to test that a TypeError is thrown when RequestInit's signal
+  // member does not implement the AbortSignal interface. We test this because
+  // we used to use an `any` IDL type to represent RequestInit's signal member
+  // instead of `AbortSignal` due to a bug in the IDL compiler, and performed
+  // conversions manually. This test ensures that conversion were carried out
+  // properly.
   const e = TypeError();
   assert_throws(e, () => {
-    new Request('/', {signal: {}})}, 'signal');
+    new Request('/', {signal: {}})},
+    'An empty object as RequestInit\'s signal member should fail type conversion');
   assert_throws(e, () => {
-    new Request('/', {signal: new Request('/')})}, 'signal');
+    new Request('/', {signal: new Request('/')})},
+    'A Request object as RequestInit\'s signal member should fail type conversion');
   assert_throws(e, () => {
-    new Request('/', {signal: new Response('/')})}, 'signal');
+    new Request('/', {signal: new Response('/')})},
+    'A Response object as RequestInit\'s signal member should fail type conversion');
 }, 'TypeError should be thrown when RequestInit\'s signal member does not implement the AbortSignal interface');
 
 promise_test(function() {

third_party/blink/renderer/core/fetch/request.cc

@@ -450,20 +450,8 @@ Request* Request::CreateRequestWithRequestOrString(
   }
 
   // "If |init|'s signal member is present, then set |signal| to it."
-  v8::Local<v8::Value> init_signal =
-      init.hasSignal() ? init.signal().V8Value() : v8::Local<v8::Value>();
-  if (!init_signal.IsEmpty()) {
-    if (init_signal->IsNull()) {
-      // This allows a null AbortSignal to override |input_request|'s, which
-      // would otherwise be used.
-      signal = nullptr;
-    } else {
-      signal = NativeValueTraits<AbortSignal>::NativeValue(
-          script_state->GetIsolate(), init_signal, exception_state);
-      if (exception_state.HadException()) {
-        return nullptr;
-      }
-    }
+  if (init.hasSignal()) {
+    signal = init.signal();
   }
 
   // "Let |r| be a new Request object associated with |request| and a new

third_party/blink/renderer/core/fetch/request_init.idl

@@ -22,9 +22,7 @@ dictionary RequestInit {
     DOMString integrity;
     boolean keepalive;
     [RuntimeEnabled=PriorityHints] RequestImportance importance;
-    // TODO(domfarolino): use AbortSignal? type for signal member once
-    // http://crrev.com/c/1113176 is merged.
-    any signal;
+    AbortSignal? signal;
     // TODO(domfarolino): add support for RequestInit window member.
     //any window; // can only be set to null
 };