toString() shouldn't disturb repeating groups #890 (#892)

* toString() shouldn't disturb repeating groups #890

* Remove trailing whitespace

* Ugh, removed more whitespace

Author: spoerri

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/java/JavaGenerator.java

@@ -3475,6 +3475,9 @@ private void appendDecoderDisplay(
             final String groupName = formatPropertyName(groupToken.name());
             final String groupDecoderName = decoderName(groupToken.name());
 
+            append(sb, indent, "int " + groupName + "OriginalOffset = " + groupName + ".offset;");
+            append(sb, indent, "int " + groupName + "OriginalIndex = " + groupName + ".index;");
+
             append(
                 sb, indent, "builder.append(\"" + groupName + Separator.KEY_VALUE + Separator.BEGIN_GROUP + "\");");
             append(sb, indent, groupDecoderName + " " + groupName + " = " + groupName + "();");
@@ -3489,6 +3492,9 @@ private void appendDecoderDisplay(
             append(sb, indent, "}");
             Separator.END_GROUP.appendToGeneratedBuilder(sb, indent);
 
+            append(sb, indent, groupName + ".offset = " + groupName + "OriginalOffset;");
+            append(sb, indent, groupName + ".index = " + groupName + "OriginalIndex;");
+
             lengthBeforeLastGeneratedSeparator = sb.length();
             Separator.FIELD.appendToGeneratedBuilder(sb, indent);