With the new Minecraft launcher, is there a way to change the .minecraft folder without manually specifying the Java path for every profile?

I am aware of the –workDir command line option, and I am using it to change the location of the .minecraft folder. However, any profile I try to launch does not find the javaw.exe file (which is found in the workDir folder, as it should be in runtimejre-x64binjavaw.exe). It throws the following error:

Unable to locate the Java runtime.
Error details: The operation completed successfully.

Filename on disk: 
Path: .
Exists: Directory

If I manually specify the javaw.exe location, then it works. My question is, why should I have to specify the javaw.exe file if it’s in the default location already in the current workDir?