8326099: GZIPOutputStream should use Deflater.getBytesRead() instead of Deflater.getTotalIn()

Reviewed-by: jpai

Author: Eirik Bjørsnøs

src/java.base/share/classes/java/util/zip/GZIPOutputStream.java

@@ -212,7 +212,9 @@ private void writeHeader() throws IOException {
      */
     private void writeTrailer(byte[] buf, int offset) throws IOException {
         writeInt((int)crc.getValue(), buf, offset); // CRC-32 of uncompr. data
-        writeInt(def.getTotalIn(), buf, offset + 4); // Number of uncompr. bytes
+        // RFC 1952: Size of the original (uncompressed) input data modulo 2^32
+        int iSize = (int) def.getBytesRead();
+        writeInt(iSize, buf, offset + 4);
     }
 
     /*