Optimize performance

[samdark]

Before:

\Yiisoft\Definitions\Benchmark\DefinitionStorageBench

    benchSetAndGet..........................R1 I6 - Mo0.929μs (±1.08%)
    benchHas................................R1 I6 - Mo0.727μs (±3.03%)
    benchSetMultipleDefinitions.............R3 I9 - Mo1.660μs (±0.92%)
    benchGetBuildStack......................R2 I6 - Mo1.971μs (±2.10%)

After:

\Yiisoft\Definitions\Benchmark\DefinitionStorageBench

    benchSetAndGet..........................R1 I0 - Mo0.770μs (±0.70%)
    benchHas................................R1 I8 - Mo0.597μs (±2.40%)
    benchSetMultipleDefinitions.............R2 I7 - Mo1.239μs (±1.62%)
    benchGetBuildStack......................R2 I9 - Mo1.847μs (±3.34%)

[xepozz]

????

[samdark]

Yeah. "Optimization". Tests pass, so "why not" :) I'll revert it.

[vjik]

Seems, all changes break logic.

Yii Definitions package doesn't contain enough tests. Any changes should be tested in Yii DI also.

[samdark]

I think it doesn't worth trying to fix this code.