Split initial methods of left/right/top/bottom on ComputedStyle.

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 772 matching lines @@
       interpolable: true,
       keywords: ["thin", "medium", "thick"],
       supports_percentage: true,
       typedom_types: ["Length"],
     },
     {
       name: "bottom",
       api_class: "CSSPropertyAPIMargin",
       api_methods: ["parseSingleValue"],
       converter: "ConvertLengthOrAuto",
-      initial: "InitialOffset",
       interpolable: true,
       keywords: ["auto"],
       supports_percentage: true,
       typedom_types: ["Length"],
     },
     {
       name: "box-shadow",
       converter: "ConvertShadowList",
       interpolable: true,
     },
@@ skipping 382 matching lines @@
       api_methods: ["parseSingleValue"],
       converter: "ConvertSelfOrDefaultAlignmentData",
       initial: "InitialSelfAlignment",
       runtime_flag: "CSSGridLayout",
     },
     {
       name: "left",
       api_class: "CSSPropertyAPIMargin",
       api_methods: ["parseSingleValue"],
       converter: "ConvertLengthOrAuto",
-      initial: "InitialOffset",
       interpolable: true,
       keywords: ["auto"],
       supports_percentage: true,
       typedom_types: ["Length"],
     },
     {
       name: "letter-spacing",
       api_class: "CSSPropertyAPILetterAndWordSpacing",
       api_methods: ["parseSingleValue"],
       converter: "ConvertSpacing",
@@ skipping 379 matching lines @@
     },
     {
       name: "resize",
       custom_value: true,
     },
     {
       name: "right",
       api_class: "CSSPropertyAPIMargin",
       api_methods: ["parseSingleValue"],
       converter: "ConvertLengthOrAuto",
-      initial: "InitialOffset",
       interpolable: true,
       keywords: ["auto"],
       supports_percentage: true,
       typedom_types: ["Length"],
     },
     {
       name: "r",
       api_class: "CSSPropertyAPIStrokeOrLength",
       converter: "ConvertLength",
       interpolable: true,
@@ skipping 298 matching lines @@
       api_methods: ["parseSingleValue"],
       inherited: true,
       runtime_flag: "CSS3TextDecorations",
       type_name: "TextUnderlinePosition",
     },
     {
       name: "top",
       api_class: "CSSPropertyAPIMargin",
       api_methods: ["parseSingleValue"],
       converter: "ConvertLengthOrAuto",
-      initial: "InitialOffset",
       interpolable: true,
       keywords: ["auto"],
       supports_percentage: true,
       typedom_types: ["Length"],
     },
     {
       name: "touch-action",
       api_class: true,
       api_methods: ["parseSingleValue"],
       converter: "ConvertFlags<TouchAction>",
@@ skipping 1267 matching lines @@
     {
       name: "-webkit-transition-timing-function",
       alias_for: "transition-timing-function",
     },
     {
       name: "-webkit-user-select",
       alias_for: "user-select",
     },
   ],
 }