Make ComputedStyle::InheritFrom group independent.

third_party/WebKit/Source/core/style/ComputedStyle.cpp

Index: third_party/WebKit/Source/core/style/ComputedStyle.cpp
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.cpp b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
index f4ddbc24d241a7349c12a07fae6013710d75b2be..b13c148a871d257039c2ce3500e72dfa8ee61536 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.cpp
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
@@ -312,19 +312,19 @@ ContentDistributionType ComputedStyle::ResolvedAlignContentDistribution(
 
 void ComputedStyle::InheritFrom(const ComputedStyle& inherit_parent,
                                 IsAtShadowBoundary is_at_shadow_boundary) {
+  EUserModify current_user_modify = UserModify();
+
   ComputedStyleBase::InheritFrom(inherit_parent, is_at_shadow_boundary);

[alancutter (OOO until 2018), 2017/05/09 00:09:18]

Unrelated to this patch: Why does this function take is_at_shadow_boundary? It
doesn't appear to use it.

[shend, 2017/05/09 00:16:02]

I think ComputedStyleBase::InheritFrom was created as a direct copy of
ComputedStyle::InheritFrom, in case we want to replace ComputedStyle with
ComputedStyleBase. IMO, such an endeavour is very complicated and I don't think
it's worth. So in the near future, no, is_at_shadow_boundary does not need to be
in ComputedStyleBase::InheritFrom.

+  rare_inherited_data_ = inherit_parent.rare_inherited_data_;
+  inherited_data_ = inherit_parent.inherited_data_;
+  if (svg_style_ != inherit_parent.svg_style_)
+    svg_style_.Access()->InheritFrom(inherit_parent.svg_style_.Get());
+
   if (is_at_shadow_boundary == kAtShadowBoundary) {
     // Even if surrounding content is user-editable, shadow DOM should act as a
     // single unit, and not necessarily be editable
-    EUserModify current_user_modify = UserModify();
-    rare_inherited_data_ = inherit_parent.rare_inherited_data_;
     SetUserModify(current_user_modify);
-  } else {
-    rare_inherited_data_ = inherit_parent.rare_inherited_data_;
   }
-  inherited_data_ = inherit_parent.inherited_data_;
-  if (svg_style_ != inherit_parent.svg_style_)
-    svg_style_.Access()->InheritFrom(inherit_parent.svg_style_.Get());
 }
 
 void ComputedStyle::CopyNonInheritedFromCached(const ComputedStyle& other) {