Merged from trunk 9741:9774

   Merged from trunk 9741:9774

   | 9742    | When reading and writing the Packages index file, translate  |
   | zmedico | metadata keys on the fly. Current translations: DESC         |
   |         | DESCRIPTION REPO repository                                  |

   | 9743    | For repoman, only cache the metadata necessary for           |
   | zmedico | visibility checks in order to reduce memory consumption.     |

   | 9744    | Remove unused iter_atoms() function.                         |
   | zmedico |                                                              |

   | 9745    | Remove the depgraph._get_arg_for_pkg() method since          |
   | zmedico | _iter_atoms_for_pkg() does the job.                          |

   | 9747    | Fix a little issue in the code from bug #197905 that causes  |
   | zmedico | some elog messages to get lost.                              |

   | 9755    | Fix --update greedy atoms logic so that it only pulls in     |
   | zmedico | packages that actually match the given atom.                 |

   | 9756    | Bug #197810 - Don't automatically downgrade packages for     |
   | zmedico | which available matching versions are masked by corruption,  |
   |         | but do automatically downgrade installed packages that       |
   |         | themselves have a valid mask such as from package.mask.      |

   | 9759    | Bug #162542 - When checking permissions inside CCACHE_DIR    |
   | zmedico | for compatibility with FEATURES=userpriv, check the          |
   |         | permissions on files inside the directory to decide whether  |
   |         | to fix the permissions.                                      |

   | 9761    | Split out a depgraph method to check if a specific new-style |
   | zmedico | virtual package exists.                                      |

   | 9762    | Make depgraph.select_files() detect when a package name      |
   | zmedico | given as an argument is ambiguous due to the existence of a  |
   |         | new-style virtual with the same name (cpv_expand() will not  |
   |         | always raise a ValueError in cases like this).               |

   | 9763    | Handle issues with newlines in elog messages that can        |
   | zmedico | trigger an unhandled ValueError to be raised from a split()  |
   |         | call inside collect_ebuild_messages(): * Use \0 to delimit   |
   |         | messages, so that that elog messages containing newlines are |
   |         | handled correctly. * Handle a potential ValueError when      |
   |         | splitting the message type.                                  |

   | 9765    | Create a new depgraph._dep_expand() method for               |
   | zmedico | select_files() to expand atoms that have no category.        |

   | 9769    | When depgraph.select_files() expands an atom category, in    |
   | zmedico | case of an old-style virtual, defer category expansion so    |
   |         | that the depgraph has more choices.                          |

   | 9771    | Make DepcheckCompositeDB cache Package instances for         |
   | zmedico | aux_get() calls.                                             |

   | 9774    | When pruning the list of parents for the slot collision      |
   | zmedico | display, always show parents that themselves have been       |
   |         | pulled into collision slots, since those are more relevant   |
   |         | that others. (branches/2.1.2 r9773)                          |

svn path=/main/branches/prefix/; revision=9806