Squashed 'libraries/gii/' content from commit e5440ea

git-subtree-dir: libraries/gii
git-subtree-split: e5440ea30f30f358741998ba635c3d3610b3e6ab
Merge commit '0678c02985c7168f574e6df2cf75775877f9de9d' as 'libraries/gii'
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