Exploit sharing when comparing and copying groups in ComputedStyle.

third_party/WebKit/Source/build/scripts/templates/ComputedStyleBase.h.tmpl

 {% from 'macros.tmpl' import license, print_if %}
-{% from 'fields/field.tmpl' import encode, getter_expression, declare_storage %}
+{% from 'fields/field.tmpl' import encode, getter_expression, declare_storage, fieldwise_compare %}
 {% from 'fields/group.tmpl' import define_field_group_class %}
 {{license()}}
 
 #ifndef ComputedStyleBase_h
 #define ComputedStyleBase_h
 
 #include "core/style/ComputedStyleConstants.h"
 #include "core/CoreExport.h"
 #include "core/style/DataRef.h"
 {% for path in include_paths %}
@@ skipping 18 matching lines @@
    } %}
 
 namespace blink {
 
 // The generated portion of ComputedStyle. For more info, see the header comment
 // in ComputedStyle.h.
 class CORE_EXPORT ComputedStyleBase {
  public:
   inline bool IndependentInheritedEqual(const ComputedStyleBase& o) const {
     return (
-    {% for field in computed_style.all_fields if field.is_inherited and field.is_independent %}
-        {{getter_expression(field)}} == o.{{getter_expression(field)}}{{print_if(not loop.last, ' &&')}}
-    {% endfor %}
+        {{fieldwise_compare(computed_style, computed_style.all_fields
+            |selectattr("is_inherited")
+            |selectattr("is_independent")
+            |list
+          )|indent(8)}}
+        true
     );
   }
 
   inline bool NonIndependentInheritedEqual(const ComputedStyleBase& o) const {
     return (
-    {% for field in computed_style.all_fields if field.is_inherited and not field.is_independent %}
-        {{getter_expression(field)}} == o.{{getter_expression(field)}}{{print_if(not loop.last, ' &&')}}
-    {% endfor %}
+        {{fieldwise_compare(computed_style, computed_style.all_fields
+            |selectattr("is_inherited")
+            |rejectattr("is_independent")
+            |list
+          )|indent(8)}}
+        true
     );
   }
 
   inline bool InheritedEqual(const ComputedStyleBase& o) const {
     return IndependentInheritedEqual(o) && NonIndependentInheritedEqual(o);
   }
 
   inline bool NonInheritedEqual(const ComputedStyleBase& o) const {
     return (
-    {% for field in computed_style.all_fields if field.is_property and not field.is_inherited %}
-        {{getter_expression(field)}} == o.{{getter_expression(field)}}{{print_if(not loop.last, ' &&')}}
-    {% endfor %}
+        {{fieldwise_compare(computed_style, computed_style.all_fields
+            |selectattr("is_property")
+            |rejectattr("is_inherited")
+            |list
+          )|indent(8)}}
+        true
     );
   }
 
   enum IsAtShadowBoundary {
     kAtShadowBoundary,
     kNotAtShadowBoundary,
   };
   void InheritFrom(const ComputedStyleBase& inheritParent,
                    IsAtShadowBoundary isAtShadowBoundary = kNotAtShadowBoundary);
 
@@ skipping 49 matching lines @@
 
  private:
   {% for field in computed_style.fields %}
   {{declare_storage(field)}}
   {% endfor %}
 };
 
 } // namespace blink
 
 #endif // ComputedStyleBase_h