These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 0.97 s (backtrack: 0/20).

[ebuild  N     ] media-libs/libyuv-1909:0/1909::gentoo  USE="-test" 456 KiB

Total: 1 package (1 new), Size of downloads: 456 KiB