widening: remove pointless code for second changegroup The caller passes in common==heads, so we will never find any nodes to visit in this code and there will therefore never be a second changegroup emitted. Differential Revision: https://phab.mercurial-scm.org/D7095

widening: remove always-true condition in widening code The function is now specifically about widening, so we don't need to check if we're widening. Differential Revision: https://phab.mercurial-scm.org/D7094

narrow: drop server support for widening using the getbundle command (BC) The client still supports widening using the getbundle, which we (Google) still depend on a for a little while more (we've started the migration to the new narrow_widen command, but we're not done yet). Differential Revision: https://phab.mercurial-scm.org/D7093

widening: duplicate generateellipsesbundle2() for widening The widening and the non-widening code are quite different. It will be clearer to have them as sepearate functions. To start with, I've just copied it exactly, so it's clearer over the next few patches how they're different. The new function should gradually become more similar to bundle2.widen_bundle(), and should perhaps eventually be merged with that function. However, I've left it in narrowbundle2.py for now since it still depends on constants like _KILLNODESIGNAL there. Differential Revision: https://phab.mercurial-scm.org/D7092

tests: show graph log before and after widening in more cases I'm about to make some changes to which revisions get sent during widening. Some more tests will make it clearer what changes. I've also switched to graph log so we easily notice if the graph shape changes. Differential Revision: https://phab.mercurial-scm.org/D7091

tracing: add a couple of trace points on obsolete and repoview I was seeing weird stalls in some fast commands, and these trace events help explain them. Differential Revision: https://phab.mercurial-scm.org/D6550