Because it seems Android is becoming a risky "enterprise" for OEMs, after the MSFT tax on Android, OEMs are not willing to pay an Apple tax. Google should have cleared any potential issue, but they are too bold. They tried when they bought Motorola but this strategy is not working that well.
I think the implication is that they work around the patents or license them.
There are obviously a load of problems with that - the later is problematic as Apple have shown little interest in licensing much of this stuff. The former because some of them cover genuinely useful stuff that compromises the product if you remove it.
They may also have decided that Samsung make fortunes so perhaps they could deal with this themselves...
