Add background-clip: border-area (#24333)

* Add `background-clip: border-area`

Supported since STP 202: https://webkit.org/blog/15798/release-notes-for-safari-technology-preview-202/

* Update background-clip.json

css/properties/background-clip.json

@@ -101,6 +101,42 @@
             "deprecated": false
           }
         },
+        "border-area": {
+          "__compat": {
+            "spec_url": "https://drafts.csswg.org/css-backgrounds-4/#valdef-background-clip-border-area",
+            "tags": [
+              "web-features:background-clip-border-area"
+            ],
+            "support": {
+              "chrome": {
+                "version_added": false
+              },
+              "chrome_android": "mirror",
+              "edge": "mirror",
+              "firefox": {
+                "version_added": false
+              },
+              "firefox_android": "mirror",
+              "ie": {
+                "version_added": false
+              },
+              "oculus": "mirror",
+              "opera": "mirror",
+              "opera_android": "mirror",
+              "safari": {
+                "version_added": "preview"
+              },
+              "safari_ios": "mirror",
+              "samsunginternet_android": "mirror",
+              "webview_android": "mirror"
+            },
+            "status": {
+              "experimental": false,
+              "standard_track": true,
+              "deprecated": false
+            }
+          }
+        },
         "border-box": {
           "__compat": {
             "spec_url": "https://drafts.csswg.org/css-backgrounds/#valdef-background-clip-border-box",
@@ -224,6 +260,7 @@
         },
         "text": {
           "__compat": {
+            "spec_url": "https://drafts.csswg.org/css-backgrounds-4/#valdef-background-clip-text",
             "tags": [
               "web-features:background-clip-text"
             ],