AS3 API completion dropped from 76% to 72% overnight

[torokati44]

It looks like a lot more methods are now reported as missing that weren't before.
My suspicion is that #17771 caused this somehow.

See this diff of the missing API report from nightly-2024-09-04 to nightly-2024-09-04:

--- avm2_report_nightly-2024-09-04.json	2024-09-06 11:55:07.660134518 +0200
+++ avm2_report_nightly-2024-09-05.json	2024-09-06 11:55:11.439135117 +0200
@@ -1,8 +1,8 @@
 {
   "summary": {
     "max_points": 4560,
-    "impl_points": 3786,
-    "stub_penalty": 316
+    "impl_points": 3598,
+    "stub_penalty": 315
   },
   "classes": {
     "flash.events.MouseEvent": {
@@ -250,19 +250,42 @@
     "RegExp": {
       "summary": {
         "max_points": 14,
-        "impl_points": 14,
+        "impl_points": 12,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "exec()",
+        "test()"
+      ],
       "stubbed": []
     },
     "String": {
       "summary": {
         "max_points": 42,
-        "impl_points": 42,
+        "impl_points": 23,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "toUpperCase()",
+        "charCodeAt()",
+        "search()",
+        "concat()",
+        "slice()",
+        "match()",
+        "valueOf()",
+        "charAt()",
+        "substr()",
+        "toString()",
+        "toLocaleLowerCase()",
+        "indexOf()",
+        "replace()",
+        "split()",
+        "substring()",
+        "lastIndexOf()",
+        "toLocaleUpperCase()",
+        "localeCompare()",
+        "toLowerCase()"
+      ],
       "stubbed": []
     },
     "flash.security.X500DistinguishedName": {
@@ -522,12 +545,50 @@
     "XMLList": {
       "summary": {
         "max_points": 82,
-        "impl_points": 77,
+        "impl_points": 39,
         "stub_penalty": 0
       },
       "missing": [
+        "setNamespace()",
+        "parent()",
+        "child()",
+        "elements()",
+        "setChildren()",
+        "hasComplexContent()",
+        "inScopeNamespaces()",
+        "toJSON()",
+        "toString()",
+        "attributes()",
+        "insertChildBefore()",
+        "removeNamespace()",
+        "children()",
+        "name()",
+        "processingInstructions()",
+        "descendants()",
+        "copy()",
+        "prependChild()",
+        "contains()",
         "propertyIsEnumerable()",
+        "normalize()",
+        "appendChild()",
+        "hasSimpleContent()",
+        "valueOf()",
+        "addNamespace()",
+        "nodeKind()",
+        "namespace()",
+        "attribute()",
+        "insertChildAfter()",
+        "namespaceDeclarations()",
+        "text()",
+        "childIndex()",
         "hasOwnProperty()",
+        "toXMLString()",
+        "replace()",
+        "comments()",
+        "setLocalName()",
+        "setName()",
+        "localName()",
+        "length()",
         "prototype.propertyIsEnumerable()",
         "prototype.valueOf",
         "prototype.hasOwnProperty()"
@@ -579,11 +640,12 @@
     "Namespace": {
       "summary": {
         "max_points": 8,
-        "impl_points": 6,
+        "impl_points": 5,
         "stub_penalty": 0
       },
       "missing": [
         "valueOf()",
+        "toString()",
         "prototype.valueOf()"
       ],
       "stubbed": []
@@ -922,10 +984,13 @@
     "QName": {
       "summary": {
         "max_points": 7,
-        "impl_points": 7,
+        "impl_points": 5,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "valueOf()",
+        "toString()"
+      ],
       "stubbed": []
     },
     "flash.media.AVTagData": {
@@ -2910,10 +2975,16 @@
     "Number": {
       "summary": {
         "max_points": 18,
-        "impl_points": 18,
+        "impl_points": 13,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "toFixed()",
+        "valueOf()",
+        "toExponential()",
+        "toString()",
+        "toPrecision()"
+      ],
       "stubbed": []
     },
     "flash.display.ShaderPrecision": {
@@ -3384,10 +3455,13 @@
     "Boolean": {
       "summary": {
         "max_points": 6,
-        "impl_points": 6,
+        "impl_points": 4,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "valueOf()",
+        "toString()"
+      ],
       "stubbed": []
     },
     "flash.events.GesturePhase": {
@@ -3464,19 +3538,60 @@
     "XML": {
       "summary": {
         "max_points": 92,
-        "impl_points": 87,
-        "stub_penalty": 1
+        "impl_points": 44,
+        "stub_penalty": 0
       },
       "missing": [
+        "setNamespace()",
+        "parent()",
+        "child()",
+        "elements()",
+        "setChildren()",
+        "hasComplexContent()",
+        "inScopeNamespaces()",
+        "toJSON()",
+        "toString()",
+        "attributes()",
+        "insertChildBefore()",
+        "removeNamespace()",
+        "children()",
+        "setNotification()",
+        "name()",
+        "processingInstructions()",
+        "notification()",
+        "descendants()",
+        "copy()",
+        "prependChild()",
+        "contains()",
         "propertyIsEnumerable()",
+        "normalize()",
+        "appendChild()",
+        "hasSimpleContent()",
+        "addNamespace()",
+        "namespace()",
+        "namespaceDeclarations()",
+        "nodeKind()",
+        "attribute()",
+        "insertChildAfter()",
+        "setLocalName()",
+        "text()",
+        "childIndex()",
         "hasOwnProperty()",
+        "replace()",
+        "setName()",
+        "comments()",
+        "toXMLString()",
+        "valueOf()",
+        "localName()",
+        "length()",
+        "static setSettings()",
+        "static settings()",
+        "static defaultSettings()",
         "prototype.propertyIsEnumerable()",
         "prototype.valueOf",
         "prototype.hasOwnProperty()"
       ],
-      "stubbed": [
-        "setNotification()"
-      ]
+      "stubbed": []
     },
     "flash.text.engine.TextJustifier": {
       "summary": {
@@ -4154,10 +4269,14 @@
     "Object": {
       "summary": {
         "max_points": 12,
-        "impl_points": 12,
+        "impl_points": 9,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "isPrototypeOf()",
+        "hasOwnProperty()",
+        "propertyIsEnumerable()"
+      ],
       "stubbed": []
     },
     "flash.text.TextSnapshot": {
@@ -4191,10 +4310,12 @@
     "Function": {
       "summary": {
         "max_points": 10,
-        "impl_points": 6,
+        "impl_points": 4,
         "stub_penalty": 0
       },
       "missing": [
+        "call()",
+        "apply()",
         "prototype.toLocaleString()",
         "prototype.call()",
         "prototype.apply()",
@@ -4874,10 +4995,31 @@
     "Array": {
       "summary": {
         "max_points": 48,
-        "impl_points": 48,
+        "impl_points": 28,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "every()",
+        "push()",
+        "unshift()",
+        "shift()",
+        "concat()",
+        "slice()",
+        "sort()",
+        "map()",
+        "removeAt()",
+        "reverse()",
+        "some()",
+        "join()",
+        "indexOf()",
+        "forEach()",
+        "insertAt()",
+        "lastIndexOf()",
+        "filter()",
+        "sortOn()",
+        "pop()",
+        "splice()"
+      ],
       "stubbed": []
     },
     "flash.text.TextColorType": {
@@ -4981,10 +5123,16 @@
     "uint": {
       "summary": {
         "max_points": 15,
-        "impl_points": 15,
+        "impl_points": 10,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "toFixed()",
+        "valueOf()",
+        "toExponential()",
+        "toString()",
+        "toPrecision()"
+      ],
       "stubbed": []
     },
     "flash.events.SoftKeyboardTrigger": {
@@ -5147,10 +5295,51 @@
     "Date": {
       "summary": {
         "max_points": 105,
-        "impl_points": 104,
+        "impl_points": 63,
         "stub_penalty": 0
       },
       "missing": [
+        "getDate()",
+        "toTimeString()",
+        "getDay()",
+        "setDate()",
+        "getTime()",
+        "getUTCDate()",
+        "toLocaleTimeString()",
+        "valueOf()",
+        "getTimezoneOffset()",
+        "toLocaleString()",
+        "getMilliseconds()",
+        "setMilliseconds()",
+        "setUTCMonth()",
+        "getUTCDay()",
+        "getSeconds()",
+        "getMonth()",
+        "setUTCSeconds()",
+        "setMonth()",
+        "getUTCSeconds()",
+        "getUTCMonth()",
+        "toUTCString()",
+        "toString()",
+        "setFullYear()",
+        "setUTCMinutes()",
+        "getUTCFullYear()",
+        "getUTCMilliseconds()",
+        "setUTCHours()",
+        "setTime()",
+        "getUTCMinutes()",
+        "toDateString()",
+        "setUTCFullYear()",
+        "setMinutes()",
+        "setUTCMilliseconds()",
+        "setUTCDate()",
+        "getMinutes()",
+        "getHours()",
+        "setHours()",
+        "getFullYear()",
+        "getUTCHours()",
+        "toLocaleDateString()",
+        "setSeconds()",
         "prototype.toJSON()"
       ],
       "stubbed": []
@@ -5331,10 +5520,16 @@
     "int": {
       "summary": {
         "max_points": 15,
-        "impl_points": 15,
+        "impl_points": 10,
         "stub_penalty": 0
       },
-      "missing": [],
+      "missing": [
+        "toFixed()",
+        "valueOf()",
+        "toExponential()",
+        "toString()",
+        "toPrecision()"
+      ],
       "stubbed": []
     },
     "flash.text.engine.TextLineMirrorRegion": {