Generate diffs for fields in ComputedStyle that use their public getters

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

Index: third_party/WebKit/Source/core/css/ComputedStyleDiffFunctions.json5
diff --git a/third_party/WebKit/Source/core/css/ComputedStyleDiffFunctions.json5 b/third_party/WebKit/Source/core/css/ComputedStyleDiffFunctions.json5
index 657b33ec5bcaa4b9a225a4c41a886dcde3c94528..ca079c94684b2610eb9b341da8c782c79b980220 100644
--- a/third_party/WebKit/Source/core/css/ComputedStyleDiffFunctions.json5
+++ b/third_party/WebKit/Source/core/css/ComputedStyleDiffFunctions.json5
@@ -8,6 +8,15 @@
     // The fields that need to be diffed.
     fields: {
     },
+
+    // A map of expressions to diff (these can be public getters of fields or 
+    // functions that use fields to determine a value).
+    // Keys are the expressions to be called. 
+    // Values are the fields associated with those expression. 
+    // This is as one field can be associated with multiple expressions.
+    map_of_expressions: {
+      default: {},
+    },
   },
   data: [
     {
@@ -19,7 +28,11 @@
     {
         name: "DiffNeedsFullLayoutAndPaintInvalidation",
         fields: ["padding-top", "padding-left", "padding-right", 
-                "padding-bottom"]
+                "padding-bottom"],
+        map_of_expressions: {"BorderLeftWidth()": "border-left-width", 
+                            "BorderTopWidth()": "border-top-width",
+                            "BorderBottomWidth()": "border-bottom-width",
+                            "BorderRightWidth()": "border-right-width"}
     }
   ],
 }