tests: fix a test case to not create conflicts This is the test case where we are testing about divergence resolution of stack of patches. If the stack is as follows: C1 C2 | | B1 B2 | | A1 A2 \/ base And A1-A2, B1-B2 and C1-C2 are content-divergent, and merging A1-A2 results in conflicts. Now if you resolve conflicts and continue resoling B1-B2, the conflicts of A1-A2 will still be there. We need somehow to understand the work we has done and not create conflicts again. To test the evolution functionality for now, we make sure conflicts does not occur.

evolve: introduce a resolutionparent variable and store it in evolvestate This patch introduces a resolutionparent variable which will be the parent of final changeset after resolving content-divergent changesets. Till now, the parent is always the parent of one of the divergent node, but now in upcoming cases, it can be a successor of both the parents of divergent nodes.

evolve: introduce a dirstatedance() fn to fix dirstate after parent change This patch introduces a dirstatedance() function which will be used after fixing the dirstate when we change parents using repo.dirstate.setparents(). Look at docs added for more details.