[C++ hidl-gen] Fix multi-dimensional arrays, vectors of arrays.

Bug: 31438033
Change-Id: I254e8bfeb8fbf665dd3836825aa271603be6d14c
diff --git a/StringType.h b/StringType.h
index 9b7cb04..9062d90 100644
--- a/StringType.h
+++ b/StringType.h
@@ -44,6 +44,7 @@
 
     void emitReaderWriterEmbedded(
             Formatter &out,
+            size_t depth,
             const std::string &name,
             bool nameIsPointer,
             const std::string &parcelObj,