Merging dives causes dives to be redowloaded

[Dirk Hohndel]

> On Aug 3, 2020, at 1:14 AM, Chirana Gheorghita Eugeniu Theodor via subsurface <subsurface at subsurface-divelog.org> wrote:
> 
> Hello,
> Speaking only about android version below:
> I did not use the merge feature until recently and I have observed some weird things:
> 1. when you do a merge dive a event appears as gas change in the profile
> 2. After merging the dives when I do download from dc original dives get re-downloaded

I hope that Linus will respond to this part as he is far more familiar with the merge code

> Another thing I observed recently is that my petrel os seen as Petrel 2 even if I select petrel and the pairing also detects it as petrel. I tried changing the name of the dc in the pairing section of Android and still in the connection section of Subsurface the name is still Petrel 2. Tryed forgetting the dive computers in Subsurface. Same thing. I attach some scrn shots.

There is an interesting oddity that the Petrel and Petrel 2 have an overlap in model information.
So they both show up as Petrel on Bluetooth, and even their HW model numbers aren't internally distinct.
So from a Subsurface / libdivecomputer perspective, they are the same.

/D