TextControl NG: Add runtime flags

This CL adds two flags, LayoutNGTextArea for <input> and
LayoutNGTextField for <textarea>. They depend on EditingNG flag.

SearchFieldCancelButtonElement and EditingViewPortElement refer to
LayoutNGTextField flag because only <input> uses them.

Both of <input> and <textarea> use TextControlInnerEditorElement.
So its TypeShouldForceLegacyLayout() checks the host element type.

This CL has no behavior changes. These flags are not enabled yet.

Bug: 1040826
Change-Id: I1caf433edb57ab2fec21c17744eff166d0a4deee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2444636Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813188}

third_party/blink/renderer/core/html/forms/html_text_area_element.cc

@@ -214,10 +214,16 @@ void HTMLTextAreaElement::ParseAttribute(
   }
 }
 
+bool HTMLTextAreaElement::TypeShouldForceLegacyLayout() const {
+  if (RuntimeEnabledFeatures::LayoutNGTextAreaEnabled())
+    return false;
+  UseCounter::Count(GetDocument(), WebFeature::kLegacyLayoutByTextControl);
+  return true;
+}
+
 LayoutObject* HTMLTextAreaElement::CreateLayoutObject(
     const ComputedStyle& style,
     LegacyLayout legacy) {
-  UseCounter::Count(GetDocument(), WebFeature::kLegacyLayoutByTextControl);
   return LayoutObjectFactory::CreateTextControlMultiLine(*this, style, legacy);
 }
 

third_party/blink/renderer/core/html/forms/html_text_area_element.h

@@ -117,7 +117,7 @@ class CORE_EXPORT HTMLTextAreaElement final : public TextControlElement {
       const QualifiedName&,
       const AtomicString&,
       MutableCSSPropertyValueSet*) override;
-  bool TypeShouldForceLegacyLayout() const override { return true; }
+  bool TypeShouldForceLegacyLayout() const override;
   LayoutObject* CreateLayoutObject(const ComputedStyle&, LegacyLayout) override;
   void AppendToFormData(FormData&) override;
   void ResetImpl() override;

third_party/blink/renderer/core/html/forms/text_control_inner_elements.cc

@@ -64,6 +64,10 @@ EditingViewPortElement::CustomStyleForLayoutObject() {
   return style;
 }
 
+bool EditingViewPortElement::TypeShouldForceLegacyLayout() const {
+  return !RuntimeEnabledFeatures::LayoutNGTextFieldEnabled();
+}
+
 // ---------------------------
 
 TextControlInnerEditorElement::TextControlInnerEditorElement(Document& document)
@@ -118,6 +122,12 @@ void TextControlInnerEditorElement::FocusChanged() {
                                              style_change_reason::kControl));
 }
 
+bool TextControlInnerEditorElement::TypeShouldForceLegacyLayout() const {
+  if (OwnerShadowHost()->HasTagName(html_names::kInputTag))
+    return !RuntimeEnabledFeatures::LayoutNGTextFieldEnabled();
+  return !RuntimeEnabledFeatures::LayoutNGTextAreaEnabled();
+}
+
 LayoutObject* TextControlInnerEditorElement::CreateLayoutObject(
     const ComputedStyle& style,
     LegacyLayout legacy) {
@@ -241,6 +251,10 @@ bool SearchFieldCancelButtonElement::WillRespondToMouseClickEvents() {
   return HTMLDivElement::WillRespondToMouseClickEvents();
 }
 
+bool SearchFieldCancelButtonElement::TypeShouldForceLegacyLayout() const {
+  return !RuntimeEnabledFeatures::LayoutNGTextFieldEnabled();
+}
+
 // ----------------------------
 
 PasswordRevealButtonElement::PasswordRevealButtonElement(Document& document)

third_party/blink/renderer/core/html/forms/text_control_inner_elements.h

@@ -40,7 +40,7 @@ class EditingViewPortElement final : public HTMLDivElement {
   scoped_refptr<ComputedStyle> CustomStyleForLayoutObject() override;
 
  private:
-  bool TypeShouldForceLegacyLayout() const final { return true; }
+  bool TypeShouldForceLegacyLayout() const final;
   bool SupportsFocus() const override { return false; }
 };
 
@@ -56,7 +56,7 @@ class TextControlInnerEditorElement final : public HTMLDivElement {
 
  private:
   LayoutObject* CreateLayoutObject(const ComputedStyle&, LegacyLayout) override;
-  bool TypeShouldForceLegacyLayout() const final { return true; }
+  bool TypeShouldForceLegacyLayout() const final;
   scoped_refptr<ComputedStyle> CustomStyleForLayoutObject() override;
   bool SupportsFocus() const override { return false; }
   bool is_visible_ = true;
@@ -70,7 +70,7 @@ class SearchFieldCancelButtonElement final : public HTMLDivElement {
   bool WillRespondToMouseClickEvents() override;
 
  private:
-  bool TypeShouldForceLegacyLayout() const final { return true; }
+  bool TypeShouldForceLegacyLayout() const final;
   bool SupportsFocus() const override { return false; }
 };
 

third_party/blink/renderer/core/html/forms/text_field_input_type.cc

@@ -277,14 +277,16 @@ void TextFieldInputType::CustomStyleForLayoutObject(ComputedStyle& style) {
 }
 
 bool TextFieldInputType::TypeShouldForceLegacyLayout() const {
+  if (RuntimeEnabledFeatures::LayoutNGTextFieldEnabled())
+    return false;
+  UseCounter::Count(GetElement().GetDocument(),
+                    WebFeature::kLegacyLayoutByTextControl);
   return true;
 }
 
 LayoutObject* TextFieldInputType::CreateLayoutObject(
     const ComputedStyle& style,
     LegacyLayout legacy) const {
-  UseCounter::Count(GetElement().GetDocument(),
-                    WebFeature::kLegacyLayoutByTextControl);
   return LayoutObjectFactory::CreateTextControlSingleLine(GetElement(), style,
                                                           legacy);
 }

third_party/blink/renderer/platform/runtime_enabled_features.json5

@@ -1034,6 +1034,14 @@
     {
       name: "LayoutNGTable",
     },
+    {
+      name: "LayoutNGTextArea",
+      depends_on: ["EditingNG"],
+    },
+    {
+      name: "LayoutNGTextField",
+      depends_on: ["EditingNG"],
+    },
     {
       // Adds the "sources" attribute to the LayoutShift interface for the
       // Layout Instability API (bit.ly/cls-sources).