Generate subgroup StyleSurroundData in ComputedStyle.

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

 {% from 'macros.tmpl' import license %}
+{% from 'fields/field.tmpl' import get_expr, set_expr %}
 {{license()}}
 
 #include "core/ComputedStyleBase.h"
 #include "wtf/SizeAssertions.h"
 
 namespace blink {
 
 struct SameSizeAsComputedStyleBase {

[meade_UTC10, 2017/04/06 03:29:57]

Did we end up making a decision about whether or not to keep this, and instead
rely on the assert in the generator?

[shend, 2017/04/06 04:39:40]

I think the decision with this was to make a CL to remove it and we can discuss
there.

For the python assert, I now remember why I deleted it. Because of groups, this
assert now needs to be on a per group basis. This then means that the
"extra_padding" variable (we set it to nonzero in case the packing is not
optimal) has to be per group as well, which is kind of ugly imo. I guess we
could warn instead of hard erroring, but that could get annoying real quick. I
don't know if it's worth keeping the python assert.

-  {% for field in fields|rejectattr("is_bit_field") %}
+  {% if computed_style.subgroups is defined %}
+  void* dataRefs[{{computed_style.subgroups|length}}];
+  {% endif %}
+  {% for field in computed_style.fields|rejectattr("is_bit_field") %}
   {{field.type_name}} {{field.name}}};
   {% endfor %}
-  unsigned m_bit_fields[{{expected_bit_field_bytes}}];
+  unsigned m_bit_fields[{{computed_style.num_bit_field_buckets}}];
 };
+
 // If this fails, the packing algorithm in make_computed_style_base.py has
 // failed to produce the optimal packed size. To fix, update the algorithm to
 // ensure that the buckets are placed so that each takes up at most 1 word.
 ASSERT_SIZE(ComputedStyleBase, SameSizeAsComputedStyleBase);
 
 void ComputedStyleBase::inheritFrom(const ComputedStyleBase& inheritParent,
                                     IsAtShadowBoundary isAtShadowBoundary) {
-  {% for field in fields if field.is_inherited %}
-  {{field.name}} = inheritParent.{{field.name}};
+  {% for field in computed_style.all_fields if field.is_inherited %}
+  {{set_expr(field)}} = inheritParent.{{get_expr(field)}};
   {% endfor %}
 }
 
 void ComputedStyleBase::copyNonInheritedFromCached(
     const ComputedStyleBase& other) {
-  {% for field in fields if (field.is_property and not field.is_inherited) or field.is_inherited_flag %}
-  {{field.name}} = other.{{field.name}};
+  {% for field in computed_style.all_fields if (field.is_property and not field.is_inherited) or field.is_inherited_flag %}
+  {{set_expr(field)}} = other.{{get_expr(field)}};
   {% endfor %}
 }
 
 void ComputedStyleBase::propagateIndependentInheritedProperties(
     const ComputedStyleBase& parentStyle) {
-  {% for field in fields if field.is_property and field.is_independent %}
+  {% for field in computed_style.all_fields if field.is_property and field.is_independent %}
   if ({{field.is_inherited_method_name}}())
-    {{field.setter_method_name}}(parentStyle.{{field.getter_method_name}}());
+    {{set_expr(field)}} = parentStyle.{{get_expr(field)}};
   {% endfor %}
 }
 
 } // namespace blink