web page usability: after POST, redirect to somewhere useful

[warner]

The human-oriented web interfaces (specifically the POST t=mkdir and t=upload forms) should leave the user's browser on a useful page. This desired behavior is different from what a programmatic client (using PUT or DELETE) ought to get.

Something regressed recently. On 0.4.0-145 (as running on our testnet), when you use the "Create a new directory" button, you are brought back to the original page (and get to notice the new directory line appear in the list). When you use the "Upload a file" button, you are also brought back to the original page (and get to notice the new file line in the list).

In 0.4.0-229 (current trunk), both operations dump you on a page that contains the URI of the newly created object, which is all-but-useless for a human.

I think this needs to be fixed back to its earlier behavior. The "Create new directory" button should perhaps drop you on the newly-created directory.. I'm not sure which behavior would be more useful.

[warner]

Fixed, in 31bfb3950a12a65a: this broke when I fixed the memory footprint problems in 3bc708529f6a64cb because the when_done= argument that was meant to get us to the right place shows up in a POST field rather than as a query argument (this is just how we happened to construct those forms.. with some hackery we could have stuffed them in the action= URL instead). 3bc708529f6a64cb means that fields no longer show up in request.args, so we weren't noticing the when_done value and thus were not doing the intended redirect.