Fix touchless.css

Previously, we hadn't applied this style via LayoutTheme, but this
appears to be normative (cf. mac.css).

touchless.css also contained a universal rule, which tripped a
DCHECK, and I've also slightly qualified it in this CL.

Bug: 961026
Change-Id: I0626299f7dee1c0c5a8b04e506d6feae05f80663
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1600960
Commit-Queue: Ian Vollick <vollick@chromium.org>
Reviewed-by: David Bokan <bokan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659192}

third_party/blink/renderer/core/css/css_default_style_sheets.cc

@@ -121,10 +121,6 @@ void CSSDefaultStyleSheets::InitializeDefaultStyles() {
   default_style_->AddRulesFromSheet(DefaultStyleSheet(), ScreenEval());
   default_print_style_->AddRulesFromSheet(DefaultStyleSheet(), PrintEval());
   default_quirks_style_->AddRulesFromSheet(QuirksStyleSheet(), ScreenEval());
-
-#if defined(ENABLE_TOUCHLESS_UASTYLE_THEME)
-  EnsureDefaultStyleSheetForTouchless();
-#endif
 }
 
 RuleSet* CSSDefaultStyleSheets::DefaultViewSourceStyle() {
@@ -218,20 +214,6 @@ void CSSDefaultStyleSheets::EnsureDefaultStyleSheetForFullscreen() {
                                            ScreenEval());
 }
 
-void CSSDefaultStyleSheets::EnsureDefaultStyleSheetForTouchless() {
-  if (touchless_style_sheet_)
-    return;
-
-  String touchless_rules = GetDataResourceAsASCIIString("touchless.css");
-  if (touchless_rules.IsEmpty())
-    return;
-
-  touchless_style_sheet_ = ParseUASheet(touchless_rules);
-  default_style_->AddRulesFromSheet(touchless_style_sheet_.Get(), ScreenEval());
-  default_quirks_style_->AddRulesFromSheet(touchless_style_sheet_.Get(),
-                                           ScreenEval());
-}
-
 void CSSDefaultStyleSheets::Trace(blink::Visitor* visitor) {
   visitor->Trace(default_style_);
   visitor->Trace(default_quirks_style_);
@@ -246,7 +228,6 @@ void CSSDefaultStyleSheets::Trace(blink::Visitor* visitor) {
   visitor->Trace(mathml_style_sheet_);
   visitor->Trace(media_controls_style_sheet_);
   visitor->Trace(fullscreen_style_sheet_);
-  visitor->Trace(touchless_style_sheet_);
 }
 
 }  // namespace blink

third_party/blink/renderer/core/css/css_default_style_sheets.h

@@ -46,7 +46,6 @@ class CSSDefaultStyleSheets
 
   bool EnsureDefaultStyleSheetsForElement(const Element&);
   void EnsureDefaultStyleSheetForFullscreen();
-  void EnsureDefaultStyleSheetForTouchless();
 
   RuleSet* DefaultStyle() { return default_style_.Get(); }
   RuleSet* DefaultQuirksStyle() { return default_quirks_style_.Get(); }
@@ -105,7 +104,6 @@ class CSSDefaultStyleSheets
   Member<StyleSheetContents> mathml_style_sheet_;
   Member<StyleSheetContents> media_controls_style_sheet_;
   Member<StyleSheetContents> fullscreen_style_sheet_;
-  Member<StyleSheetContents> touchless_style_sheet_;
 
   std::unique_ptr<UAStyleSheetLoader> media_controls_style_sheet_loader_;
   DISALLOW_COPY_AND_ASSIGN(CSSDefaultStyleSheets);

third_party/blink/renderer/core/css/touchless.css

@@ -29,7 +29,3 @@ video:-internal-spatial-navigation-interest {
 body {
     user-select: none !important;
 }
-
-* {
-    -webkit-user-drag: none !important;
-}

third_party/blink/renderer/core/layout/layout_theme_touchless.cc

@@ -4,6 +4,8 @@
 
 #include "third_party/blink/renderer/core/layout/layout_theme_touchless.h"
 
+#include "third_party/blink/renderer/platform/data_resource_helper.h"
+
 namespace blink {
 
 scoped_refptr<LayoutTheme> LayoutThemeTouchless::Create() {
@@ -18,6 +20,11 @@ LayoutTheme& LayoutTheme::NativeTheme() {
 
 LayoutThemeTouchless::~LayoutThemeTouchless() {}
 
+String LayoutThemeTouchless::ExtraDefaultStyleSheet() {
+  return LayoutThemeMobile::ExtraDefaultStyleSheet() +
+         GetDataResourceAsASCIIString("touchless.css");
+}
+
 bool LayoutThemeTouchless::IsFocusRingOutset() const {
   return true;
 }

third_party/blink/renderer/core/layout/layout_theme_touchless.h

@@ -14,6 +14,7 @@ class LayoutThemeTouchless final : public LayoutThemeMobile {
   static scoped_refptr<LayoutTheme> Create();
   bool DelegatesMenuListRendering() const override { return true; }
 
+  String ExtraDefaultStyleSheet() override;
   bool IsFocusRingOutset() const override;
 
  private: