Merged from trunk -r12704:12715

   Merged from trunk -r12704:12715

   | 12705    | Bug #259882 - Disable the ignore-previously-merged option   |
   | zmedico  | by default since emerge's confmem already provides similar  |
   |          | functionality which is a little safer.                      |

   | 12706    | In mirror_cache(), normalize EAPI by mapping EAPI=0 to      |
   | zmedico  | empty.                                                      |

   | 12707    | Implement lazy evaluation of USE_EXPAND variables in        |
   | zmedico  | config.setcpv(), since those variables are only needed when |
   |          | an ebuild shell is spawned. Thanks to Marat Radchenko       |
   |          | <slonopotamusorama@gmail.com> for testing this patch. He    |
   |          | reports a 14% reduction in the time consumed for `emerge    |
   |          | -vpe world` on an ARM device (from 3m12.008s to 2m45.055s). |

   | 12708    | Fix typo in DepPriority.__str__().                          |
   | zmedico  |                                                             |

   | 12709    | Implement BlockerDepPriority.__str__().                     |
   | zmedico  |                                                             |

   | 12710    | Inside depgraph._merge_order_bias(), promote deep system    |
   | zmedico  | runtime deps toward the front of the merge list. This       |
   |          | should help optimize merge order to account for implicit    |
   |          | system dependencies.                                        |

   | 12711    | Remove stray parenthesis.                                   |
   | zmedico  |                                                             |

   | 12712    | reject all set*id binaries that have DT_RPATH:$ORIGIN       |
   | SpankMan | #260331                                                     |

   | 12713    | Bug #259954 - Do not spawn parallel build when the system   |
   | zmedico  | is in a fragile state due to a system package having an     |
   |          | unsatisfied runtime dependency (such as sys-libs/pam having |
   |          | an unsatisfied PDEPEND on sys-auth/pambase).                |

   | 12714    | In traversing deps to add to                                |
   | zmedico  | Scheduler._unsatisfied_system_deps, only traverse completed |
   |          | 'merge' nodes since those are the only ones that need to be |
   |          | checked for unsatisfied runtime deps, and it's normal for   |
   |          | nodes that aren't yet complete to have unsatisfied runtime  |
   |          | deps.                                                       |

   | 12715    | Remove recursion code from                                  |
   | zmedico  | Scheduler._system_merge_started() since indirect deps are   |
   |          | checked when the corresponding parent is merged.            |

svn path=/main/branches/prefix/; revision=12762