Reland "Adds slotAssignmentMode to the shadow root bindings."

This is a reland of 63c4f9f5

The problem with the reverted CL is that a binding file needs updating.
third_party/blink/renderer/bindings/generated_in_core.gni should be
manually updated to point to the newly generated binding classes.
The reason CQ and my local didn't catch this is because the old
generated files v8_shadow_root_slotting(.h|.cc) still exists. But a
clean build will fail.

This CL is the reverted CL plus updates to generated_in_core.gni. See
patch 1 for the failed case. Patch 2 has the update and failed try job
passes.

Original change's description:
> Adds slotAssignmentMode to the shadow root bindings.
>
> Prior to this CL, the previous implementation of imperative slot API uses
> 'slotting' as an optional parameter for Element.attachShadow(). However,
> based on the feedback by JanMiksovsky@ in
> https://github.com/w3c/webcomponents/pull/866, the parameter should be
> changed to 'slotAssignment' to make it align with other members,
> assignNodes(), assignElements(). I agree with this feedback.
>
> This CL updates the following:
> 1. update bindings where the previous 'slotting' was used to
>  'slotAssignment'.
> 2. Updated the enum type of slotAssignment. It should be,
>  SlotAssignmentMode [auto | manual].
> 3. Added attribute 'slotAssignment' to Shadow_Root.idl and updated
>  global-interface-listing-expected.txt.
> 4. Modify existing tests from using slotting to slotAssignment.
> 5. Removed test that'll be covered by
>  external/wpt/shadow-dom/slots-imperative-slot-api.tentative.html.
> https://chromium-review.googlesource.com/c/chromium/src/+/2083742
> I'll update this CL with the correct
>  slots-imperative-slot-api.tentative-expected.txt once that CL lands.
>
> Bug: 869308
> Change-Id: I0fb1a9e11c88d52fc0b0570f3f3e1f5bf834f858
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2084376
> Commit-Queue: Yu Han <yuzhehan@chromium.org>
> Reviewed-by: Mason Freed <masonfreed@chromium.org>
> Reviewed-by: Hayato Ito <hayato@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#748116}

Bug: 869308
Change-Id: I26121ca421d707393afc720c1c5918ff36373f29
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2096784Reviewed-by: Mason Freed <masonfreed@chromium.org>
Reviewed-by: Hayato Ito <hayato@chromium.org>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Commit-Queue: Yu Han <yuzhehan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#749215}

third_party/blink/perf_tests/shadow_dom/custom-detail-summary.js

@@ -11,7 +11,7 @@ customElements.define("my-summary", MySummaryElement);
 customElements.define("my-detail", class extends HTMLElement {
   constructor() {
     super();
-    this.attachShadow({ mode: "open", slotting: "manual" });
+    this.attachShadow({ mode: "open", slotAssignment: "manual" });
   }
   connectedCallback() {
     const target = this;

third_party/blink/perf_tests/shadow_dom/declarative-api.html

@@ -4,7 +4,7 @@
 </div>
 <script>
   const host = document.querySelector("#host");
-  const shadow_root = host.attachShadow({ mode: 'open', slotting: 'auto' });
+  const shadow_root = host.attachShadow({ mode: 'open', slotAssignment: 'auto' });
   const slot1 = document.createElement("slot");
   const child1 = document.createElement("child");
   shadow_root.appendChild(slot1);

third_party/blink/perf_tests/shadow_dom/imperative-api-appendchild.html

@@ -4,7 +4,7 @@
 </div>
 <script>
   const host = document.querySelector("#host");
-  const shadow_root = host.attachShadow({ mode: 'open', slotting: 'manual' });
+  const shadow_root = host.attachShadow({ mode: 'open', slotAssignment: 'manual' });
   const slot1 = document.createElement("slot");
   const child1 = document.createElement("child");
   slot1.assign([child1]);

third_party/blink/perf_tests/shadow_dom/imperative-api-assign.html

@@ -4,7 +4,7 @@
 </div>
 <script>
   const host = document.querySelector("#host");
-  const shadow_root = host.attachShadow({ mode: 'open', slotting: 'manual' });
+  const shadow_root = host.attachShadow({ mode: 'open', slotAssignment: 'manual' });
   const slot1 = document.createElement("slot");
   const child1 = document.createElement("child");
   shadow_root.appendChild(slot1);

third_party/blink/perf_tests/shadow_dom/imperative-api-assigned-elements.html

@@ -4,7 +4,7 @@
 </div>
 <script>
   const host = document.querySelector("#host");
-  const shadow_root = host.attachShadow({ mode: 'open', slotting: 'manual' });
+  const shadow_root = host.attachShadow({ mode: 'open', slotAssignment: 'manual' });
   const slot1 = document.createElement("slot");
   const child1 = document.createElement("child");
   slot1.assign([child1]);

third_party/blink/perf_tests/shadow_dom/imperative-api-assigned-slot.html

@@ -4,7 +4,7 @@
 </div>
 <script>
   const host = document.querySelector("#host");
-  const shadow_root = host.attachShadow({ mode: 'open', slotting: 'manual' });
+  const shadow_root = host.attachShadow({ mode: 'open', slotAssignment: 'manual' });
   const slot1 = document.createElement("slot");
   const child1 = document.createElement("child");
   slot1.assign([child1]);

third_party/blink/perf_tests/shadow_dom/imperative-api-insertbefore.html

@@ -5,7 +5,7 @@
 </div>
 <script>
   const host = document.querySelector("#host");
-  const shadow_root = host.attachShadow({ mode: 'open', slotting: 'manual' });
+  const shadow_root = host.attachShadow({ mode: 'open', slotAssignment: 'manual' });
   const slot1 = document.createElement("slot");
   const child1 = document.createElement("child");
   const child = document.querySelector("#child");

third_party/blink/perf_tests/shadow_dom/imperative-api.html

@@ -6,7 +6,7 @@
 <script>
   const host = document.querySelector("#host");
   const child1 = document.querySelector("#child1");
-  const shadow_root = host.attachShadow({ mode: "open", slotting: "manual" });
+  const shadow_root = host.attachShadow({ mode: "open", slotAssignment: "manual" });
   window.onload = function() {
     PerfTestRunner.measureTime({
       description: "Measure performance of slot assignment in manual-slotting mode in shadow root.",

third_party/blink/renderer/bindings/generated_in_core.gni

@@ -107,8 +107,8 @@ generated_enumeration_sources_in_core = [
   "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_selection_mode.h",
   "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_shadow_root_mode.cc",
   "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_shadow_root_mode.h",
-  "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_shadow_root_slotting_mode.cc",
-  "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_shadow_root_slotting_mode.h",
+  "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_slot_assignment_mode.cc",
+  "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_slot_assignment_mode.h",
   "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_supported_type.cc",
   "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_supported_type.h",
   "$root_gen_dir/third_party/blink/renderer/bindings/core/v8/v8_text_track_kind.cc",

third_party/blink/renderer/core/dom/element.cc

@@ -3710,7 +3710,7 @@ ShadowRoot* Element::attachShadow(const ShadowRootInit* shadow_root_init_dict,
   DCHECK(!shadow_root_init_dict->hasMode() || !GetShadowRoot());
   bool delegates_focus = shadow_root_init_dict->hasDelegatesFocus() &&
                          shadow_root_init_dict->delegatesFocus();
-  bool manual_slotting = shadow_root_init_dict->slotting() == "manual";
+  bool manual_slotting = shadow_root_init_dict->slotAssignment() == "manual";
   return &AttachShadowRootInternal(type, delegates_focus, manual_slotting);
 }
 
@@ -3740,8 +3740,9 @@ ShadowRoot& Element::AttachShadowRootInternal(ShadowRootType type,
   GetDocument().SetShadowCascadeOrder(ShadowCascadeOrder::kShadowCascadeV1);
   ShadowRoot& shadow_root = CreateAndAttachShadowRoot(type);
   shadow_root.SetDelegatesFocus(delegates_focus);
-  shadow_root.SetSlotting(manual_slotting ? ShadowRootSlotting::kManual
-                                          : ShadowRootSlotting::kAuto);
+  shadow_root.SetSlotAssignmentMode(manual_slotting
+                                        ? SlotAssignmentMode::kManual
+                                        : SlotAssignmentMode::kAuto);
   return shadow_root;
 }
 

third_party/blink/renderer/core/dom/shadow_root.cc

@@ -70,7 +70,7 @@ ShadowRoot::ShadowRoot(Document& document, ShadowRootType type)
       type_(static_cast<unsigned>(type)),
       registered_with_parent_shadow_root_(false),
       delegates_focus_(false),
-      slotting_(static_cast<unsigned>(ShadowRootSlotting::kAuto)),
+      slot_assignment_mode_(static_cast<unsigned>(SlotAssignmentMode::kAuto)),
       needs_distribution_recalc_(false),
       unused_(0) {
   if (IsV0())
@@ -108,8 +108,8 @@ Node* ShadowRoot::Clone(Document&, CloneChildrenFlag) const {
   return nullptr;
 }
 
-void ShadowRoot::SetSlotting(ShadowRootSlotting slotting) {
-  slotting_ = static_cast<unsigned>(slotting);
+void ShadowRoot::SetSlotAssignmentMode(SlotAssignmentMode assignment_mode) {
+  slot_assignment_mode_ = static_cast<unsigned>(assignment_mode);
 }
 
 String ShadowRoot::innerHTML() const {

third_party/blink/renderer/core/dom/shadow_root.h

@@ -46,7 +46,7 @@ class WhitespaceAttacher;
 
 enum class ShadowRootType { V0, kOpen, kClosed, kUserAgent };
 
-enum class ShadowRootSlotting { kManual, kAuto };
+enum class SlotAssignmentMode { kManual, kAuto };
 
 class CORE_EXPORT ShadowRoot final : public DocumentFragment, public TreeScope {
   DEFINE_WRAPPERTYPEINFO();
@@ -146,9 +146,16 @@ class CORE_EXPORT ShadowRoot final : public DocumentFragment, public TreeScope {
   void SetDelegatesFocus(bool flag) { delegates_focus_ = flag; }
   bool delegatesFocus() const { return delegates_focus_; }
 
-  void SetSlotting(ShadowRootSlotting slotting);
-  bool IsManualSlotting() {
-    return slotting_ == static_cast<unsigned>(ShadowRootSlotting::kManual);
+  void SetSlotAssignmentMode(SlotAssignmentMode assignment);
+  bool IsManualSlotting() const {
+    return slot_assignment_mode_ ==
+           static_cast<unsigned>(SlotAssignmentMode::kManual);
+  }
+  SlotAssignmentMode GetSlotAssignmentMode() const {
+    return static_cast<SlotAssignmentMode>(slot_assignment_mode_);
+  }
+  String slotAssignment() const {
+    return IsManualSlotting() ? "manual" : "auto";
   }
 
   bool ContainsShadowRoots() const { return child_shadow_root_count_; }
@@ -181,7 +188,7 @@ class CORE_EXPORT ShadowRoot final : public DocumentFragment, public TreeScope {
   unsigned type_ : 2;
   unsigned registered_with_parent_shadow_root_ : 1;
   unsigned delegates_focus_ : 1;
-  unsigned slotting_ : 1;
+  unsigned slot_assignment_mode_ : 1;
   unsigned needs_distribution_recalc_ : 1;
   unsigned unused_ : 10;
 

third_party/blink/renderer/core/dom/shadow_root.idl

@@ -34,6 +34,7 @@ interface ShadowRoot : DocumentFragment {
     // https://crbug.com/1058762 has been fixed.
     [CEReactions, CustomElementCallbacks, RaisesException=Setter] attribute [TreatNullAs=EmptyString, StringContext=TrustedHTML] DOMString innerHTML;
     readonly attribute boolean delegatesFocus;
+    [RuntimeEnabled=ManualSlotting] readonly attribute SlotAssignmentMode slotAssignment;
 };
 
 ShadowRoot includes DocumentOrShadowRoot;

third_party/blink/renderer/core/dom/shadow_root_init.idl

@@ -5,10 +5,10 @@
 // Spec: https://w3c.github.io/webcomponents/spec/shadow/#shadowrootinit-dictionary
 
 enum ShadowRootMode { "open", "closed" };
-enum ShadowRootSlottingMode { "manual", "auto" };
+enum SlotAssignmentMode { "manual", "auto" };
 
 dictionary ShadowRootInit {
     required ShadowRootMode mode;
     boolean delegatesFocus;
-    [RuntimeEnabled=ManualSlotting] ShadowRootSlottingMode slotting;
+    [RuntimeEnabled=ManualSlotting] SlotAssignmentMode slotAssignment;
 };

third_party/blink/web_tests/external/wpt/shadow-dom/slots-imperative-slot-api.tentative-expected.txt

 This is a testharness.js-based test.
-FAIL attachShadow can take slotAssignment parameter. assert_throws_js: others should throw exception function "() => {
-    tTree.host3.attachShadow({ mode: 'open', slotAssignment: 'exceptional' })}" did not throw
+PASS attachShadow can take slotAssignment parameter.
 FAIL Imperative slot API throws exception when not slotAssignment != 'manual'. assert_throws_dom: function "() => { tTree.s1.assign([]); }" did not throw
 FAIL Imperative slot API throws exception when slotable parentNode != slot's host. assert_throws_dom: function "() => { tTree.s2.assign([tTree.c1]); }" did not throw
 FAIL Imperative slot API can assign nodes in manual slot assignment. assert_equals: expected null but got Element node <slot id="s1"></slot>

third_party/blink/web_tests/shadow-dom/crashes/imperative-api.html

@@ -12,7 +12,7 @@ See https://crbug.com/869308
 <script>
 const host = document.querySelector("#host");
 const child1 = document.querySelector("#child1");
-const shadow_root = host.attachShadow({ mode: "open", slotting: "manual" });
+const shadow_root = host.attachShadow({ mode: "open", slotAssignment: "manual" });
 const slot1 = document.createElement("slot");
 const slot2 = document.createElement("slot");
 shadow_root.appendChild(slot1);

third_party/blink/web_tests/shadow-dom/imperative-api.html

@@ -6,27 +6,11 @@ See https://crbug.com/869308
 <script src="../resources/testharness.js"></script>
 <script src="../resources/testharnessreport.js"></script>
 <script src="resources/shadow-dom.js"></script>
-<div id="test1">
-  <div id="host"></div>
-  <div id="host1"></div>
-  <div id="host2"></div>
-</div>
-<script>
-test(() => {
-  let n = createTestTree(test1);
-  assert_not_equals(n.host.attachShadow({ mode: 'open', slotting: 'manual' }),
-                    null, 'slotting manual should work');
-  assert_not_equals(n.host1.attachShadow({ mode: 'open', slotting: 'auto' }),
-                    null, 'slotting auto should work');
-  assert_throws_js(TypeError, () => {
-  n.host2.attachShadow({ mode: 'open', slotting: 'exceptional' })},
-                'others should throw exception');
-}, 'attachShadow can take slotting parameter');
 
 </script>
 <div id="test2">
   <div id="host">
-    <template id="shadow_root" data-mode="open" data-slotting="manual">
+    <template id="shadow_root" data-mode="open" data-slot-assignment="manual">
       <slot id="s1"></slot>
       <slot id="s2"></slot>
       <slot id="s3"></slot>
@@ -37,7 +21,7 @@ test(() => {
   </div>
   <div id="c4"></div>
   <div id="host4">
-    <template id="shadow_root1" data-mode="open" data-slotting="manual">
+    <template id="shadow_root1" data-mode="open" data-slot-assignment="manual">
       <slot id="s5" name="s5"></slot>
     </template>
   </div>

third_party/blink/web_tests/shadow-dom/imperative-apis/custom-detail-summary.js

@@ -11,7 +11,7 @@ customElements.define("my-summary", MySummaryElement);
 customElements.define("my-detail", class extends HTMLElement {
   constructor() {
     super();
-    this.attachShadow({ mode: "open", slotting: "manual" });
+    this.attachShadow({ mode: "open", slotAssignment: "manual" });
   }
   connectedCallback() {
     const target = this;

third_party/blink/web_tests/shadow-dom/resources/shadow-dom.js

@@ -76,10 +76,10 @@ function createTestTree(node) {
     if (template.getAttribute('data-mode') === 'v0') {
       // For legacy Shadow DOM
       shadowRoot = parent.createShadowRoot();
-    } else if (template.getAttribute('data-slotting') === 'manual') {
+    } else if (template.getAttribute('data-slot-assignment') === 'manual') {
        shadowRoot =
           parent.attachShadow({mode: template.getAttribute('data-mode'),
-                               slotting: 'manual'});
+                               slotAssignment: 'manual'});
     } else {
       shadowRoot =
           parent.attachShadow({mode: template.getAttribute('data-mode')});

third_party/blink/web_tests/webexposed/global-interface-listing-expected.txt

@@ -8030,6 +8030,7 @@ interface ShadowRoot : DocumentFragment
     getter mode
     getter pictureInPictureElement
     getter pointerLockElement
+    getter slotAssignment
     getter styleSheets
     method constructor
     method elementFromPoint