Google appears to have updated music manager to version 1.0.117.4968_beta, and removed the 1.0.113.5623_beta's deb file from their server. When testing locally (by just copying the ebuild), everything seems to be in order. Reproducible: Always
+*google-musicmanager-1.0.117.4968_beta (26 May 2014) + + 26 May 2014; Christoph Junghans <ottxor@gentoo.org> + +google-musicmanager-1.0.117.4968_beta.ebuild, + google-musicmanager-1.0.113.5623_beta.ebuild: + version bump (bug #511486) +