Allow access to locals in fileMapTokens

I would like to access locals in the custom tokens that are defined in the fileMapTokens hook. The problem that I am trying to solve is using a custom token that resolves based on what is passed in the locals.  For example I'm writing an addon that allows developers to have multiple app instances based on platform e.g. desktop, mobile, wii, etc. Currently I have a blueprint that can create sub projects under `app/` for each platform. I want to have generators that allow developers to do `ember g route profile --platform=desktop`. This will create code at `app/desktop/route/profile.js`.
Maybe move the original `customLocals` definition up, then reference that in the `fileMapVariables`? Referencing it from `fileMapVariables` seems like it could cause confusion later.
```
var customLocals = this.locals(options);
var fileMapVariables = {
    pod: this.pod,
    podPath: podPath,
    blueprintName: this.name,
    dasherizedModuleName: stringUtils.dasherize(moduleName),
    locals: customLocals
  };
```