use pdiff for Translation-* files if available (Closes: #657902)

Beware: pdiffs for Translation-* are only acquired if their
availability is advertised in the Release file.

apt-pkg/acquire-item.cc

@@ -1395,7 +1395,12 @@ void pkgAcqMetaIndex::QueueIndexes(bool verify)				/*{{{*/
 				(*Target)->ShortDesc, ExpectedIndexHash);
 	 else if (transInRelease == false || MetaIndexParser->Exists((*Target)->MetaKey) == true)
 	 {
-	    new pkgAcqIndexTrans(Owner, *Target, ExpectedIndexHash, MetaIndexParser);
+	    if (_config->FindB("Acquire::PDiffs",true) == true && transInRelease == true &&
+		MetaIndexParser->Exists(string((*Target)->MetaKey).append(".diff/Index")) == true)
+	       new pkgAcqDiffIndex(Owner, (*Target)->URI, (*Target)->Description,
+				   (*Target)->ShortDesc, ExpectedIndexHash);
+	    else
+	       new pkgAcqIndexTrans(Owner, *Target, ExpectedIndexHash, MetaIndexParser);
 	 }
 	 continue;
       }

debian/changelog

@@ -30,6 +30,7 @@ apt (0.8.16~exp13) UNRELEASED; urgency=low
   * apt-pkg/acquire-item.cc:
     - drop support for i18n/Index file (introduced in 0.8.11) and use
       the Release file instead to get the Translations (Closes: #649314)
+    - use pdiff for Translation-* files if available (Closes: #657902)
   * ftparchive/writer.cc:
     - add 'Translation-*' to the default patterns
 
@@ -54,7 +55,7 @@ apt (0.8.16~exp13) UNRELEASED; urgency=low
   * apt-pkg/contrib/fileutl.h:
     - fix compat with FileFd::OpenDescriptor() in ReadOnlyGzip mode
 
- -- David Kalnischkies <kalnischkies@gmail.com>  Sat, 18 Feb 2012 19:23:42 +0100
+ -- David Kalnischkies <kalnischkies@gmail.com>  Sat, 18 Feb 2012 19:44:16 +0100
 
 apt (0.8.16~exp12) experimental; urgency=low