bundle: commit is commiting the value of a field from the working copy instead of value at stage time

[erichanson]

When bundle.commt() executes, it is not committing the value of a field at the time it was staged, rather it is using the working copy. I sure thought it was architected to copy the value from the working copy to the stage when the staging happened, but it is not doing that, it just uses the current working copy value.

In git terms, this is the scenario where you stage a file and then make more modifications to it. When you commit, it doesn't include modifications made after it was staged unless you stage the changes again.

Investigate and fix.