[Java] Take account of header having nested composites.

Author: mjpt777

sbe-tool/src/main/java/uk/co/real_logic/sbe/ir/IrDecoder.java

@@ -119,13 +119,14 @@ private int captureHeader(final List<Token> tokens)
 
  int index = 0;
  Token token = tokens.get(index);
+ final String headerName = token.name();
  headerTokens.add(token);
  do
  {
  token = tokens.get(++index);
  headerTokens.add(token);
  }
- while (Signal.END_COMPOSITE != token.signal());
+ while (Signal.END_COMPOSITE != token.signal() || !headerName.equals(token.name()));
 
  irHeader = headerTokens;