Add support for generating external types in ComputedStyleBase.

third_party/WebKit/Source/core/css/CSSProperties.json5

 {
 // This file specifies all the CSS properties we support and the necessary
 // information for our code generation. The various supported arguments
 // are described below with example usage
 
   parameters: {
     // - alias_for: "other-property"
     // Properties specifying alias_for should be virtually identical to the
     // properties they alias. Minor parsing differences are allowed as long as
     // the CSSValues created are of the same format of the aliased property.
@@ skipping 56 matching lines @@
     // every property, since this value can be inferred from that.
     field_template: {
       valid_values: [
         // Field is stored as an enum and has a initial/getter/setter/resetter.
         "keyword",
         // Field is stored a packed boolean flag and has a initial/getter/setter/resetter.
         // TODO(shend): generalise this to "primitive"
         "flag",
         // Field is stored as a bool, whose default value is false
         // and can only be set to true. Has a initial/getter/setter.
-        "monotonic_flag"
+        "monotonic_flag",
+        // Field has type specified at field_type_path and has a getter/setter.
+        // Also has a setter taking an rvalue reference. Cannot be packed.
+        "external",
       ],
     },
 
     // - field_type_path: "path/to/Type"
     // For properties that have generated field storage in ComputedStyle,
     // this optional argument will override the field's generated type with
     // an external one specified at the given path. The type must be defined
     // in a header file at that path, and have the same name as the file.
     // Currently, only enum types are supported, and the enum's only values
     // must be CamelCase values of the keywords of the property.
     field_type_path: {
     },
 
     // - keywords: ["keyword1", "keyword2"]
     // This specifies all valid keyword values for the property.
     // TODO(sashab): Once all properties are represented here, delete
     // CSSValueKeywords.in and use this list instead.
     keywords: {
       default: [],
     },
 
-    // - initial_keyword: "keyword-value"
-    // This specifies the initial keyword value for the keyword fields.
-    initial_keyword: {
+    // - default_value: "keyword-value"
+    // This specifies the default value for this field.
+    // - for keyword fields, this is the initial keyword
+    // - for other fields, this is a string containg the C++ expression
+    //   that is used to initialise the field.
+    default_value: {
     },
 
     // Flags which go into CSSOMTypes:
     // - typedom_types: ["Type", "OtherType"]
     // The property can take types specified in typedom_types for CSS Typed OM.
     // Keyword does not need to be specified as every property can take keywords.
     // - separator
     // The property supports a list of values, and when there is more than one,
     // it is separated with this character.
     // - supports_percentage
@@ skipping 219 matching lines @@
       custom_all: true,
       inherited: true,
       interpolable: true,
       priority: "High",
     },
     {
       name: "direction",
       custom_value: true,
       field_type_path: "platform/text/TextDirection",
       inherited: true,
-      initial_keyword: "ltr",
+      default_value: "ltr",
       field_template: "keyword",
       keywords: ["ltr", "rtl"],
       priority: "High",
     },
     {
       name: "font-family",
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "convertFontFamily",
       is_descriptor: true,
@@ skipping 141 matching lines @@
       custom_value: true,
       inherited: true,
       priority: "High",
       type_name: "TextOrientation",
     },
     {
       name: "writing-mode",
       custom_value: true,
       field_type_path: "platform/text/WritingMode",
       inherited: true,
-      initial_keyword: "horizontal-tb",
+      default_value: "horizontal-tb",
       field_template: "keyword",
       keywords: ["horizontal-tb", "vertical-rl", "vertical-lr"],
       priority: "High",
       type_name: "WritingMode",
     },
     {
       name: "-webkit-writing-mode",
       custom_value: true,
       inherited: true,
       priority: "High",
@@ skipping 142 matching lines @@
       converter: "convertLineWidth<float>",
       initial: "initialBorderWidth",
       interpolable: true,
       keywords: ["thin", "medium", "thick"],
       typedom_types: ["Length"],
     },
     {
       name: "border-collapse",
       independent: true,
       inherited: true,
-      initial_keyword: "separate",
+      default_value: "separate",
       field_template: "keyword",
       keywords: ["separate", "collapse"],
     },
     {
       name: "border-image-outset",
       api_class: "CSSPropertyAPIBorderImageOutset",
       custom_all: true,
       interpolable: true,
     },
     {
@@ skipping 116 matching lines @@
     {
       name: "box-shadow",
       converter: "convertShadowList",
       interpolable: true,
     },
     "box-sizing",
     {
       name: "break-after",
       // Storage for this property also covers these legacy properties:
       // page-break-after, -webkit-column-break-after
-      initial_keyword: "auto",
+      default_value: "auto",
       field_template: "keyword",
       keywords: [
         "auto", "avoid", "avoid-column", "avoid-page", "column", "left", "page", "recto", "right", "verso"
       ],
       type_name: "EBreakBetween",
     },
     {
       name: "break-before",
       // Storage for this property also covers these legacy properties:
       // page-break-before, -webkit-column-break-before
-      initial_keyword: "auto",
+      default_value: "auto",
       field_template: "keyword",
       keywords: [
         "auto", "avoid", "avoid-column", "avoid-page", "column", "left", "page", "recto", "right", "verso"
       ],
       type_name: "EBreakBetween",
     },
     {
       name: "break-inside",
       // Storage for this property also covers these legacy properties:
       // page-break-inside, -webkit-column-break-inside
-      initial_keyword: "auto",
+      default_value: "auto",
       field_template: "keyword",
       keywords: ["auto", "avoid", "avoid-column", "avoid-page"],
     },
     {
       name: "buffered-rendering",
       svg: true,
     },
     {
       name: "caption-side",
       independent: true,
       inherited: true,
-      initial_keyword: "top",
+      default_value: "top",
       field_template: "keyword",
       keywords: ["top", "bottom", "left", "right"],
     },
     {
       name: "caret-color",
       api_class: true,
       api_methods: ["parseSingleValue"],
       custom_all: true,
       inherited: true,
       interpolable: true,
     },
     {
       name: "clear",
-      initial_keyword: "none",
+      default_value: "none",
       field_template: "keyword",
       keywords: ["none", "left", "right", "both"],
     },
     {
       name: "clip",
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "convertClip",
       custom_all: true,
       interpolable: true,
@@ skipping 63 matching lines @@
       custom_all: true,
       inherited: true,
       field_template: "keyword",
       keywords: [
         "auto", "default", "none", "context-menu", "help", "pointer", "progress", "wait", "cell", "crosshair",
         "text", "vertical-text", "alias", "copy", "move", "no-drop", "not-allowed", "e-resize", "n-resize",
         "ne-resize", "nw-resize", "s-resize", "se-resize", "sw-resize", "w-resize", "ew-resize", "ns-resize",
         "nesw-resize", "nwse-resize", "col-resize", "row-resize", "all-scroll", "zoom-in", "zoom-out",
         "-webkit-grab", "-webkit-grabbing"
       ],
-      initial_keyword: "auto",
+      default_value: "auto",
     },
     {
       name: "cx",
       api_class: "CSSPropertyAPIStrokeOrLength",
       converter: "convertLength",
       interpolable: true,
       svg: true,
     },
     {
       name: "cy",
       api_class: "CSSPropertyAPIStrokeOrLength",
       converter: "convertLength",
       interpolable: true,
       svg: true,
     },
     {
       name: "d",
       converter: "convertPathOrNone",
       interpolable: true,
       svg: true,
     },
     {
       name: "display",
-      initial_keyword: "inline",
+      default_value: "inline",
       field_template: 'keyword',
       keywords: [
         "inline", "block", "list-item", "inline-block", "table", "inline-table", "table-row-group", "table-header-group",
         "table-footer-group", "table-row", "table-column-group", "table-column", "table-cell", "table-caption", "-webkit-box",
         "-webkit-inline-box", "flex", "inline-flex", "grid", "inline-grid", "contents", "flow-root", "none",
       ],
     },
     {
       name: "dominant-baseline",
       inherited: true,
       svg: true,
     },
     {
       name: "empty-cells",
       independent: true,
       inherited: true,
-      initial_keyword: "show",
+      default_value: "show",
       field_template: "keyword",
       keywords: ["show", "hide"],
       type_name: "EEmptyCells",
     },
     {
       name: "fill",
       api_class: "CSSPropertyAPIPaintStroke",
       api_methods: ["parseSingleValue"],
       custom_all: true,
       inherited: true,
@@ skipping 38 matching lines @@
     },
     {
       name: "flex-shrink",
       api_class: "CSSPropertyAPIFlexGrowOrShrink",
       interpolable: true,
       type_name: "float",
     },
     "flex-wrap",
     {
       name: "float",
-      initial_keyword: "none",
+      default_value: "none",
       field_template: "keyword",
       keywords: ["none", "left", "right"],
       name_for_methods: "Floating",
       type_name: "EFloat",
     },
     {
       name: "flood-color",
       api_class: "CSSPropertyAPIColor",
       api_methods: ["parseSingleValue"],
       converter: "convertColor",
@@ skipping 185 matching lines @@
       api_methods: ["parseSingleValue"],
       custom_value: true,
       inherited: true,
       interpolable: true,
       typedom_types: ["Image"],
     },
     {
       name: "list-style-position",
       independent: true,
       inherited: true,
-      initial_keyword: "outside",
+      default_value: "outside",
       field_template: "keyword",
       keywords: ["outside", "inside"],
     },
     {
       name: "list-style-type",
       inherited: true,
-      initial_keyword: "disc",
+      default_value: "disc",
       field_template: "keyword",
       keywords: [
         "disc", "circle", "square", "decimal", "decimal-leading-zero", "arabic-indic", "bengali", "cambodian", "khmer", "devanagari", "gujarati", "gurmukhi", "kannada", "lao", "malayalam", "mongolian", "myanmar", "oriya", "persian", "urdu", "telugu", "tibetan", "thai", "lower-roman", "upper-roman", "lower-greek", "lower-alpha", "lower-latin", "upper-alpha", "upper-latin", "cjk-earthly-branch", "cjk-heavenly-stem", "ethiopic-halehame", "ethiopic-halehame-am", "ethiopic-halehame-ti-er", "ethiopic-halehame-ti-et", "hangul", "hangul-consonant", "korean-hangul-formal", "korean-hanja-formal", "korean-hanja-informal", "hebrew", "armenian", "lower-armenian", "upper-armenian", "georgian", "cjk-ideographic", "simp-chinese-formal", "simp-chinese-informal", "trad-chinese-formal", "trad-chinese-informal", "hiragana", "katakana", "hiragana-iroha", "katakana-iroha", "none",
       ],
     },
     {
       name: "margin-bottom",
       api_class: "CSSPropertyAPIMargin",
       api_methods: ["parseSingleValue"],
       converter: "convertQuirkyLength",
@@ skipping 204 matching lines @@
       name: "outline-width",
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "convertLineWidth<unsigned short>",
       interpolable: true,
     },
     {
       name: "overflow-anchor",
       runtime_flag: "ScrollAnchoring",
       inherited: false,
-      initial_keyword: "auto",
+      default_value: "auto",
       field_template: "keyword",
       keywords: [
         "visible", "none", "auto",
       ],
     },
     {
       name: "overflow-wrap",
       inherited: true,
     },
     {
       name: "overflow-x",
-      initial_keyword: "visible",
+      default_value: "visible",
       field_template: "keyword",
       keywords: [
         "visible", "hidden", "scroll", "auto", "overlay", "-webkit-paged-x", "-webkit-paged-y",
       ],
       type_name: "EOverflow",
     },
     {
       name: "overflow-y",
-      initial_keyword: "visible",
+      default_value: "visible",
       field_template: "keyword",
       keywords: [
         "visible", "hidden", "scroll", "auto", "overlay", "-webkit-paged-x", "-webkit-paged-y",
       ],
       type_name: "EOverflow",
     },
     {
       name: "padding-bottom",
       api_class: "CSSPropertyAPIPadding",
       api_methods: ["parseSingleValue"],
@@ skipping 41 matching lines @@
     },
     {
       name: "perspective-origin",
       converter: "convertPosition",
       interpolable: true,
     },
     {
       name: "pointer-events",
       independent: true,
       inherited: true,
-      initial_keyword: "auto",
+      default_value: "auto",
       field_template: "keyword",
       keywords: [
         "none", "auto", "stroke", "fill", "painted", "visible", "visibleStroke", "visibleFill", "visiblePainted", "bounding-box", "all",
       ],
     },
     {
       name: "position",
       custom_inherit: true,
-      initial_keyword: "static",
+      default_value: "static",
       field_template: "keyword",
       keywords: [
         "static", "relative", "absolute", "fixed", "sticky",
       ],
     },
     {
       name: "quotes",
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "convertQuotes",
@@ skipping 187 matching lines @@
     {
       name: "stroke-width",
       api_class: "CSSPropertyAPIStrokeOrLength",
       converter: "convertUnzoomedLength",
       inherited: true,
       interpolable: true,
       svg: true,
     },
     {
       name: "table-layout",
-      initial_keyword: "auto",
+      default_value: "auto",
       field_template: "keyword",
       keywords: [
         "auto", "fixed"
       ]
     },
     {
       name: "tab-size",
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "convertLengthOrTabSpaces",
       inherited: true,
       type_name: "TabSize",
     },
     {
       name: "text-align",
       custom_value: true,
       independent: true,
       inherited: true,
-      initial_keyword: "start",
+      default_value: "start",
       field_template: "keyword",
       keywords: [
         "left", "right", "center", "justify", "webkitLeft", "webkitRight", "webkitCenter", "start", "end",
       ],
     },
     {
       name: "text-align-last",
       inherited: true,
       type_name: "TextAlignLast",
     },
@@ skipping 75 matching lines @@
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "convertTextSizeAdjust",
       inherited: true,
       type_name: "TextSizeAdjust",
     },
     {
       name: "text-transform",
       independent: true,
       inherited: true,
-      initial_keyword: "none",
+      default_value: "none",
       field_template: "keyword",
       keywords: ["capitalize", "uppercase", "lowercase", "none"],
     },
     {
       name: "text-underline-position",
       api_class: true,
       api_methods: ["parseSingleValue"],
       inherited: true,
       runtime_flag: "CSS3TextDecorations",
       type_name: "TextUnderlinePosition",
@@ skipping 54 matching lines @@
       name: "scale",
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "convertScale",
       interpolable: true,
       runtime_flag: "CSSIndependentTransformProperties",
     },
     {
       name: "unicode-bidi",
       field_type_path: "platform/text/UnicodeBidi",
-      initial_keyword: "normal",
+      default_value: "normal",
       field_template: "keyword",
       keywords: [
         "normal", "embed", "bidi-override", "isolate", "plaintext", "isolate-override",
       ],
       type_name: "UnicodeBidi",
     },
     {
       name: "vector-effect",
       svg: true,
     },
     {
       name: "vertical-align",
       api_class: true,
       api_methods: ["parseSingleValue"],
       custom_inherit: true,
       custom_value: true,
       interpolable: true,
     },
     {
       name: "visibility",
       independent: true,
       inherited: true,
-      initial_keyword: "visible",
+      default_value: "visible",
       interpolable: true,
       field_template: "keyword",
       keywords: ["visible", "hidden", "collapse"],
     },
     {
       name: "x",
       api_class: "CSSPropertyAPIStrokeOrLength",
       converter: "convertLength",
       interpolable: true,
       svg: true,
@@ skipping 47 matching lines @@
     },
     {
       name: "-webkit-box-align",
       type_name: "EBoxAlignment",
     },
     "-webkit-box-decoration-break",
     {
       name: "-webkit-box-direction",
       independent: true,
       inherited: true,
-      initial_keyword: "normal",
+      default_value: "normal",
       field_template: "keyword",
       keywords: ["normal", "reverse"],
     },
     {
       name: "-webkit-box-flex",
       api_class: true,
       type_name: "float",
     },
     {
       name: "-webkit-box-flex-group",
@@ skipping 186 matching lines @@
     {
       name: "-webkit-perspective-origin-y",
       api_class: "CSSPropertyAPIWebkitOriginY",
       converter: "convertLength",
       interpolable: true,
     },
     {
       name: "-webkit-print-color-adjust",
       independent: true,
       inherited: true,
-      initial_keyword: "economy",
+      default_value: "economy",
       field_template: "keyword",
       keywords: ["economy", "exact"],
     },
     {
       name: "-webkit-rtl-ordering",
       independent: true,
       inherited: true,
       initial: "initialRtlOrdering",
-      initial_keyword: "logical",
+      default_value: "logical",
       field_template: "keyword",
       keywords: ["logical", "visual"],
       setter: "setRtlOrdering",
       type_name: "EOrder",
     },
     {
       name: "-webkit-ruby-position",
       inherited: true,
       type_name: "RubyPosition",
     },
@@ skipping 80 matching lines @@
       inherited: true,
     },
     {
       name: "user-select",
       inherited: true,
     },
     {
       name: "white-space",
       independent: true,
       inherited: true,
-      initial_keyword: "normal",
+      default_value: "normal",
       field_template: "keyword",
       keywords: ["normal", "pre", "pre-wrap", "pre-line", "nowrap", "-webkit-nowrap"],
     },
     {
       name: "widows",
       api_class: "CSSPropertyAPIFragmentation",
       api_methods: ["parseSingleValue"],
       inherited: true,
       interpolable: true,
       type_name: "short",
@@ skipping 783 matching lines @@
     {
       name: "-webkit-transition-timing-function",
       alias_for: "transition-timing-function",
     },
     {
       name: "-webkit-user-select",
       alias_for: "user-select",
     },
   ],
 }