Automatically generate EBreakBetween & EBreakInside

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 747 matching lines @@
       typedom_types: ["Length"],
     },
     {
       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",
+      keyword_only: true,
+      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",
+      keyword_only: true,
+      keywords: [
+        "auto", "avoid", "avoid-column", "avoid-page", "column", "left", "page", "recto", "right", "verso"
+      ],
       type_name: "EBreakBetween",
     },
     {
       name: "break-inside",
-      type_name: "EBreakInside",
+      // Storage for this property also covers these legacy properties:
+      // page-break-inside, -webkit-column-break-inside
+      initial_keyword: "auto",
+      keyword_only: true,
+      keywords: ["auto", "avoid", "avoid-column", "avoid-page"],
     },
     {
       name: "buffered-rendering",
       svg: true,
     },
     {
       name: "caption-side",
       independent: true,
       inherited: true,
       initial_keyword: "top",
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     {
       name: "-webkit-transition-timing-function",
       alias_for: "transition-timing-function",
     },
     {
       name: "-webkit-user-select",
       alias_for: "user-select",
     },
   ],
 }