It seems that new Opera has a dependency problem with libdbus-1-3 in the DEBIAN/control file. Opera 52 installation fix is to edit that file by removing (>= 1.9.14) after libdbus-1-3 and then build a new package. An example about building the fixed package:
1. Extract an original package
2. Edit DEBIAN/control file
3. Build a fixed package from a edited package
sudo chown root:root -R build-folder
sudo chown root:root -R opera-stable_51.0.2830.40_amd64
sudo dpkg -b build-folder fixed.deb
sudo dpkg -b opera-stable_51.0.2830.40_amd64 opera-stable_51.0.2830.40_amd64-fixed.deb
Probably automatic opera-update does not work with Mint 17, so you need to upgrade Opera by hand.
The same issue and fix works also with Linux Mint Debian (LMDE).
FINALLY the bug is fixed, and Opera install and upgrades automatically in Mint 17 and LMDE too. :)