test: smaller chunk size for smaller person.jpg

PR-URL: https://github.com/nodejs/node/pull/5813
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rod Vagg <rod@vagg.org>

test/parallel/test-zlib-params.js

@@ -6,13 +6,13 @@ var path = require('path');
 var fs = require('fs');
 
 const file = fs.readFileSync(path.resolve(common.fixturesDir, 'person.jpg'));
-const chunkSize = 24 * 1024;
+const chunkSize = 12 * 1024;
 const opts = { level: 9, strategy: zlib.Z_DEFAULT_STRATEGY };
 const deflater = zlib.createDeflate(opts);
 
 const chunk1 = file.slice(0, chunkSize);
 const chunk2 = file.slice(chunkSize);
-const blkhdr = Buffer.from([0x00, 0x48, 0x82, 0xb7, 0x7d]);
+const blkhdr = Buffer.from([0x00, 0x5a, 0x82, 0xa5, 0x7d]);
 const expected = Buffer.concat([blkhdr, chunk2]);
 let actual;