Support logging details of calls to json-prune-fetch-response

Example:

    example.com##+js(json-prune-fetch-response)

This will output to the logger details of all fetch() with a
Response.json() call.

Related discussion:
uBlockOrigin/uAssets#22556

assets/resources/scriptlets.js

@@ -1198,10 +1198,10 @@ function jsonPruneFetchResponseFn(
  const extraArgs = safe.getExtraArgs(Array.from(arguments), 2);
  const propNeedles = parsePropertiesToMatch(extraArgs.propsToMatch, 'url');
  const stackNeedle = safe.initPattern(extraArgs.stackToMatch || '', { canNegate: true });
+ const logall = rawPrunePaths === '';
  const applyHandler = function(target, thisArg, args) {
  const fetchPromise = Reflect.apply(target, thisArg, args);
- if ( rawPrunePaths === '' ) { return fetchPromise; }
- let outcome = 'match';
+ let outcome = logall ? 'nomatch' : 'match';
  if ( propNeedles.size !== 0 ) {
  const objs = [ args[0] instanceof Object ? args[0] : { url: args[0] } ];
  if ( objs[0] instanceof Request ) {
@@ -1218,14 +1218,18 @@ function jsonPruneFetchResponseFn(
  outcome = 'nomatch';
  }
  }
- if ( outcome === 'nomatch' ) { return fetchPromise; }
- if ( safe.logLevel > 1 ) {
+ if ( logall === false && outcome === 'nomatch' ) { return fetchPromise; }
+ if ( safe.logLevel > 1 && outcome !== 'nomatch' && propNeedles.size !== 0 ) {
  safe.uboLog(logPrefix, `Matched optional "propsToMatch"\n${extraArgs.propsToMatch}`);
  }
  return fetchPromise.then(responseBefore => {
  const response = responseBefore.clone();
  return response.json().then(objBefore => {
  if ( typeof objBefore !== 'object' ) { return responseBefore; }
+ if ( logall ) {
+ safe.uboLog(logPrefix, safe.JSON_stringify(objBefore, null, 2));
+ return responseBefore;
+ }
  const objAfter = objectPruneFn(
  objBefore,
  rawPrunePaths,