Simplify passing extra parameters in scriptlets

When scriptlets can receive extra optional paramaters, these will
now be passed as pair of extra paramaters in the filter declaration,
whereas each pair is a `name, value` instance.

As a result, the optional paramaters that can be passed to the
`aeld` scriptlet can be passed this way, i.e. no longer need
a JSON approach, example:

    github.com##+js(aeld, click, , log, 1)
    github.com##+js(aeld, , , runAt, idle, log, 1)

The non-optional paramaters are always positional, after which
the optional paramaters are non-positional pairs of values.

Author: gorhill

assets/resources/scriptlets.js

@@ -177,6 +177,47 @@ function runAtHtmlElement(fn) {
 
 /******************************************************************************/
 
+builtinScriptlets.push({
+    name: 'get-extra-args-entries.fn',
+    fn: getExtraArgsEntries,
+});
+function getExtraArgsEntries(args, offset) {
+    return args.slice(offset).reduce((out, v, i, a) => {
+        if ( (i & 1) === 0 ) {
+            const rawValue = a[i+1];
+            const value = /^\d+$/.test(rawValue)
+                ? parseInt(rawValue, 10)
+                : rawValue;
+            out.push([ a[i], value ]);
+        }
+        return out;
+    }, []);
+}
+
+builtinScriptlets.push({
+    name: 'get-extra-args-map.fn',
+    fn: getExtraArgsMap,
+    dependencies: [
+        'get-extra-args-entries.fn',
+    ],
+});
+function getExtraArgsMap(args, offset = 0) {
+    return new Map(getExtraArgsEntries(args, offset));
+}
+
+builtinScriptlets.push({
+    name: 'get-extra-args.fn',
+    fn: getExtraArgs,
+    dependencies: [
+        'get-extra-args-entries.fn',
+    ],
+});
+function getExtraArgs(args, offset = 0) {
+    return Object.fromEntries(getExtraArgsEntries(args, offset));
+}
+
+/******************************************************************************/
+
 builtinScriptlets.push({
     name: 'abort-current-script-core.fn',
     fn: abortCurrentScriptCore,
@@ -714,6 +755,7 @@ builtinScriptlets.push({
     aliases: [ 'aeld.js' ],
     fn: addEventListenerDefuser,
     dependencies: [
+        'get-extra-args.fn',
         'pattern-to-regex.fn',
         'run-at.fn',
         'safe-self.fn',
@@ -723,20 +765,15 @@ builtinScriptlets.push({
 });
 // https://github.com/uBlockOrigin/uAssets/issues/9123#issuecomment-848255120
 function addEventListenerDefuser(
-    arg1 = '',
-    arg2 = ''
+    type = '',
+    pattern = ''
 ) {
-    const details = typeof arg1 !== 'object'
-        ? { type: arg1, pattern: arg2 }
-        : arg1;
-    const { type = '', pattern = '' } = details;
-    if ( typeof type !== 'string' ) { return; }
-    if ( typeof pattern !== 'string' ) { return; }
+    const extraArgs = getExtraArgs(Array.from(arguments), 2);
     const safe = safeSelf();
     const reType = patternToRegex(type);
     const rePattern = patternToRegex(pattern);
-    const log = shouldLog(details);
-    const debug = shouldDebug(details);
+    const log = shouldLog(extraArgs);
+    const debug = shouldDebug(extraArgs);
     const trapEddEventListeners = ( ) => {
         const eventListenerHandler = {
             apply: function(target, thisArg, args) {
@@ -767,7 +804,7 @@ function addEventListenerDefuser(
     };
     runAt(( ) => {
         trapEddEventListeners();
-    }, details.runAt);
+    }, extraArgs.runAt);
 }
 
 /******************************************************************************/
@@ -2317,6 +2354,7 @@ builtinScriptlets.push({
     fn: sed,
     world: 'ISOLATED',
     dependencies: [
+        'get-extra-args.fn',
         'pattern-to-regex.fn',
         'run-at.fn',
         'safe-self.fn',
@@ -2329,14 +2367,9 @@ function sed(
 ) {
     const reNodeName = patternToRegex(nodeName, 'i');
     const rePattern = patternToRegex(pattern, 'gms');
-    const extraArgs = new Map(
-        Array.from(arguments).slice(3).reduce((out, v, i, a) => {
-            if ( (i & 1) === 0 ) { out.push([ a[i], a[i+1] || undefined ]); }
-            return out;
-        }, [])
-    );
-    const shouldLog = scriptletGlobals.has('canDebug') && extraArgs.get('log') || 0;
-    const reCondition = patternToRegex(extraArgs.get('condition') || '', 'gms');
+    const extraArgs = getExtraArgs(Array.from(arguments), 3);
+    const shouldLog = scriptletGlobals.has('canDebug') && extraArgs.log || 0;
+    const reCondition = patternToRegex(extraArgs.condition || '', 'gms');
     const safe = safeSelf();
     const stop = (takeRecord = true) => {
         if ( takeRecord ) {
@@ -2347,7 +2380,7 @@ function sed(
             safe.uboLog(`sed.js: quitting "${pattern}" => "${replacement}"`);
         }
     };
-    let sedCount = extraArgs.has('sedCount') ? parseInt(extraArgs.get('sedCount')) : 0;
+    let sedCount = extraArgs.sedCount || 0;
     const handleNode = node => {
         const before = node.textContent;
         if ( safe.RegExp_test.call(rePattern, before) === false ) { return true; }
@@ -2389,9 +2422,9 @@ function sed(
             safe.uboLog(`sed.js ${count} nodes present before installing mutation observer`);
         }
     }
-    if ( extraArgs.has('stay') ) { return; }
+    if ( extraArgs.stay ) { return; }
     runAt(( ) => {
-        const quitAfter = parseInt(extraArgs.get('quitAfter')) || 0;
+        const quitAfter = extraArgs.quitAfter || 0;
         if ( quitAfter !== 0 ) {
             setTimeout(( ) => { stop(); }, quitAfter);
         } else {