I'm thinking of naming the dog I got for my gf with the name she wanted for our first child
That sounds like a bad idea. Are you sure she would be okay with naming your dog after the name she picked out for your first child?
I got her a dog even though she doesn't like dogs. She's always complaining that I'm ignoring her choice.
You should talk to your gf about it and find out what she has to say. Then you can name the pet base on her feedback.
That's boring and I don't want to talk, I just want to do this.
Well getting her a dog even when she doesn't like a dog doesn't sound like you're taking her needs into consideration at all. If you do this then prepare for whatever repercussions that may follow because she will likely be upset you ignored her. When it comes to life long decisions, its better to just talk to your partner to avoid causing issues within your relationship.