don't rely on 'args' in trace, not available in 7.4

[remicollet]

Rather than adding an empty 'args' array, seems simpler to skip the full array_map / array_walk

Also fix the test suite.

PHPUnit 8.5.2 by Sebastian Bergmann and contributors.

Runtime:       PHP 7.4.3RC1
Configuration: /dev/shm/BUILD/ReflectionDocBlock-a48807183a4b819072f26e347bbd0b5199a9d15f/phpunit.xml
Error:         No code coverage driver is available

.........................WWW...................................  63 / 297 ( 21%)
............................................................... 126 / 297 ( 42%)
.........................................................S..... 189 / 297 ( 63%)
.......................................S....................... 252 / 297 ( 84%)
.............................................                   297 / 297 (100%)

Time: 113 ms, Memory: 8,00 MB

There were 3 warnings:

1) phpDocumentor\Reflection\DocBlock\StandardTagFactoryTest::testAddParameterToServiceLocator
assertAttributeSame() is deprecated and will be removed in PHPUnit 9.
readAttribute() is deprecated and will be removed in PHPUnit 9.
getObjectAttribute() is deprecated and will be removed in PHPUnit 9.

2) phpDocumentor\Reflection\DocBlock\StandardTagFactoryTest::testAddServiceToServiceLocator
assertAttributeSame() is deprecated and will be removed in PHPUnit 9.
readAttribute() is deprecated and will be removed in PHPUnit 9.
getObjectAttribute() is deprecated and will be removed in PHPUnit 9.

3) phpDocumentor\Reflection\DocBlock\StandardTagFactoryTest::testInjectConcreteServiceForInterfaceToServiceLocator
assertAttributeSame() is deprecated and will be removed in PHPUnit 9.
readAttribute() is deprecated and will be removed in PHPUnit 9.
getObjectAttribute() is deprecated and will be removed in PHPUnit 9.

--

There were 2 skipped tests:

1) phpDocumentor\Reflection\DocBlock\Tags\ReturnTest::testFactoryMethodWithGenericWithSpaceAndAddedEmojisToVerifyMultiByteBehaviour
A bug in the TypeResolver breaks this test

/dev/shm/BUILD/ReflectionDocBlock-a48807183a4b819072f26e347bbd0b5199a9d15f/tests/unit/DocBlock/Tags/ReturnTest.php:202

2) phpDocumentor\Reflection\DocBlock\Tags\ThrowsTest::testFactoryMethodWithGenericWithSpaceAndAddedEmojisToVerifyMultiByteBehaviour
A bug in the TypeResolver breaks this test

/dev/shm/BUILD/ReflectionDocBlock-a48807183a4b819072f26e347bbd0b5199a9d15f/tests/unit/DocBlock/Tags/ThrowsTest.php:202

WARNINGS!
Tests: 297, Assertions: 487, Warnings: 3, Skipped: 2.

[jaapio]

Thanks for this optimization!