One of the debug committers, Pawel Piech, has been working on creating a debug context breadcrumb. A cool feature that we are all looking forward too. The current patch applies nicely to the debug ui project, but there is a need to try out the feature in your main Eclipse environment. Self-hosting isn't practical for everyone. There are a couple of ways of doing this in 3.5:
1) Hack them in :) Export the bundles, put them in your install directory, rename them to have the same name and version as the previously installed bundles and start with -clean. This will trick p2 into loading the new code and treating it the same as the previous bundles. This is not a great choice as you are working behind p2's back so if there are any problems, you are on your own.
2) Use the new PDE one step export and install feature. Simply go to File > Export... > PDE > Deployable Plug-ins and Fragments. Then in the wizard, choose the last radio button "Install into running application". This will build your workspace bundles and use p2 to install them into your host application. Assuming all goes well, you'll have your code up and running and you can uninstall the changes using p2's UI (Help > Installation Information).
3) Create a feature patch. While option 2 is the fastest for developers, feature patches allow you to provide the changes via an update site. Users will be able to install without ever checking out any code from CVS. My next blog post will explain the basics of creating a feature patch.