I worked in a specific direction without communicating it to master's thesis advisor, problem? I am currently waiting for a meeting with my master's thesis supervisor and two people from a research institution i am associated with. The plan is to for me to talk about my literature review, and suggest possible directions for my thesis.
In a previous meeting with my supervisor only, we have already decided on a topic, but the method or framework are subject to the outcome of the next meeting. Since the research institution has a closely related industry project, it is to be expected that the decision process will be in some way influenced by the applicability to the project. To some people, this might be a limitation, but I would be glad to see parts of my work actually being useful.
I have prepared slides to give an overview of my literature search, along with suggestions on what to do next. Because I have not been too busy with other stuff, I have also implemented some methods already. In addition, I am currently working on deriving the extension of another method to our specific problem, which may or may not work. While it could be nice to have this kind of progression, I'm not sure whether it is appropriate of me to work in a direction without having checked with my supervisor first. This is especially since we might decide to do something entirely different.
I expect the supervisor to be in favor of methods that are similar to recent publications, and the research institute people to be biased towards methods that fit their project. I think the methods I have been looking at are rather geared towards the latter.
My questions are:

Should I bring up me working on selected methods in the meeting? This could be interpreted as going against our agreement to decide on a method together.
Should I update my supervisor on my progress prior to the meeting (via e-mail)?
Would it be a bad idea to steer the meeting into the direction of the methods I have  been working on, without mentioning it?

My concerns are not only having worked on the wrong things in vain, but also upsetting my supervisor for not checking in and not abiding the agreement (at least kind of).
I would rather not embarrass him in front of the other people, in case he would feel that way about me working without having communicated with him.

Additional Information: my relationship to my supervisor is somewhat formal since we haven't had too much contact up until now, but I already know both people from the research institution where I have been a research assistant for over two years.
It isn't a problem unless you make it a problem. I would think that what you have done shows initiative and would be praised normally. That should be true even if the committee suggests that you go in another direction for the thesis.
But, to me, at least, saying that you have been exploring one of the options seriously would be a point in your favor. But if other considerations are such that you should be taking another direction now, you can do that, and not insist that you follow up now on your current direction.
If they suggest a different direction, just put the recent work away for a while. You might have the opportunity to develop it further later and the experience of doing it might actually help in following up on the suggested direction.
As long as you don't fight with people, who might have good ideas as well as authority over you, then you should be fine. Maybe better than fine. Initiative is a good thing.
Likewise, a quick update to your supervisor on your recent activities should not be an issue as long as you are flexible.