app-crypt/seahorse-3.6.3
app-crypt/seahorse-sharing-3.6.1
app-editors/gedit-3.6.2-r1
app-editors/gedit-plugins-3.6.1-r1
dev-libs/libgdata-0.13.3
dev-libs/libgweather-3.6.2
dev-libs/totem-pl-parser-3.4.3-r1

All of the above were removed from the portage tree, and their 3.8.x updates are masked.

with the following unmasked, they compile fine:

net-libs/libsoup-2.42.2-r1
dev-libs/libpeas-1.8.1
dev-libs/atk-2.8.0
x11-libs/gtk+-3.8.2