openjdk-8 backport not installable

[Dominic Hargreaves <dom@earth.li>]

Hi Emmanuel,

Was openjdk-8 8u45-b14-2~bpo8+1 actually built on jessie? openjdk-8-jre,
for example, appears to depend on libjpeg8 which isn't in jessie. By
comparison, my local no-change[1] rebuild of openjdk-8 on a clean jessie
sbuild depends instead on libjpeg62-turbo.

Thanks for your work on this backport, which I think will be very useful.

Cheers,
Dominic.

[1] excepting swapping the openjdk-7/openjdk-8 build depends around to
    keep sbuild happy