Fix various bugs in test cases

[anba]

• src/class-elements/prod-private-async-method.case

• test/language/expressions/class/private-methods/prod-private-async-method.js

• test/language/statements/class/private-methods/prod-private-async-method.js

  • Use the value argument instead of calling #m() again, because the latter returns a new Promise object.

• test/built-ins/Array/prototype/flatMap/non-callable-argument-throws.js

  • assert(...) requires a boolean argument, switch to assert.sameValue(...)

• test/built-ins/Reflect/ownKeys/return-on-corresponding-order-large-index.js

  • Update test case per Normative: Use array indices instead of integer indices in OrdinaryOwnPropertyKeys ecma262#1242
  • Also add 4294967294 (maximum array index) and 4294967295 (not an array index) while there.

• test/intl402/NumberFormat/currencyDisplay-unit.js

  • The option value is "narrow-symbol" instead of "narrowSymbol".

• test/intl402/NumberFormat/style-unit.js

  • "unit" style without a unit value leads to a TypeError, use the "generic" unit here.

• test/intl402/Segmenter/iterator/following.js

• test/intl402/Segmenter/iterator/preceding.js

  • Remove | 0 to ensure we actually test the ToIndex operation in the following resp. preceding methods.
  • ToIndex(1.4) is 1, so don't expect a TypeError for iter.preceding(1.4)

• test/intl402/Segmenter/iterator/granularity.js

• test/intl402/Segmenter/prototype/segment/segment-line.js

• test/intl402/Segmenter/prototype/segment/segment-sentence.js

• test/intl402/Segmenter/prototype/segment/segment-word.js

  • The initial value for breakType is always undefined.

[leobalter]

Thanks for all the fixes!

[leobalter]

oops! Thanks again for catching this!