Don't check version field from local ZIP header

Our current Maven based Java toolchain produces JARs, which
have a different "version needed to extract" in the ZIP local
and central directory header.

I had a look at 7zip and unzip and they already ignore the version
but compare other data LO already ignores - sig. The "standard"
document from PKWARE doesn't help.

So just compare the file path and calculate the data offset and
otherwise ignore all (duplicated) information from the local index
and rely on a correct central directory entry. Various programs
produce(d) "broken" ZIP files; even LO at some point (see git log).

Change-Id: I8d63abb0d49a1087c7654f401b62355c147c3118
Reviewed-on: https://gerrit.libreoffice.org/19779Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>

package/source/zipapi/ZipFile.cxx

@@ -639,10 +639,15 @@ bool ZipFile::readLOC( ZipEntry &rEntry )
 
     aGrabber.seek(nPos);
     sal_Int32 nTestSig = aGrabber.ReadInt32();
-
     if (nTestSig != LOCSIG)
         throw ZipIOException("Invalid LOC header (bad signature)" );
-    sal_Int16 nVersion = aGrabber.ReadInt16();
+
+    // Ignore all (duplicated) information from the local file header.
+    // various programs produced "broken" zip files; even LO at some point.
+    // Just verify the path and calculate the data offset and otherwise
+    // rely on the central directory info.
+
+    aGrabber.ReadInt16(); //version
     aGrabber.ReadInt16(); //flag
     aGrabber.ReadInt16(); //how
     aGrabber.ReadInt32(); //time
@@ -682,18 +687,7 @@ bool ZipFile::readLOC( ZipEntry &rEntry )
             rEntry.sPath = sLOCPath;
         }
 
-        // check basic local file header / entry consistency, just
-        // plain ignore bits 1 & 2 of the flag field - they are either
-        // purely informative, or even fully undefined (depending on
-        // nMethod)
-        // Do *not* compare nMethod / nHow, older versions with
-        // encrypted streams write mismatching DEFLATE/STORE pairs
-        // there.
-        // Do *not* compare timestamps, since MSO 2010 can produce documents
-        // with timestamp difference in the central directory entry and local
-        // file header.
-        bBroken = rEntry.nVersion != nVersion
-                        || rEntry.nPathLen != nPathLen
+        bBroken = rEntry.nPathLen != nPathLen
                         || !rEntry.sPath.equals( sLOCPath );
     }
     catch(...)