Change CBC_DataMatrixWriter::Encode() to return a vector.

Also make out parameters pointers, instead of non-const references.

Change-Id: Idf28d1bbfce43a0c23b5aac30c78cb79ad5e5c4d
Reviewed-on: https://pdfium-review.googlesource.com/c/46515
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>

fxbarcode/datamatrix/BC_DataMatrixWriter.h

diff --git a/fxbarcode/datamatrix/BC_DataMatrixWriter.h b/fxbarcode/datamatrix/BC_DataMatrixWriter.h
index f3dcc55..f95612e 100644
--- a/fxbarcode/datamatrix/BC_DataMatrixWriter.h
+++ b/fxbarcode/datamatrix/BC_DataMatrixWriter.h
@@ -7,6 +7,8 @@
 #ifndef FXBARCODE_DATAMATRIX_BC_DATAMATRIXWRITER_H_
 #define FXBARCODE_DATAMATRIX_BC_DATAMATRIXWRITER_H_
 
+#include <vector>
+
 #include "fxbarcode/BC_TwoDimWriter.h"
 
 class CBC_DataMatrixWriter final : public CBC_TwoDimWriter {
@@ -14,9 +16,9 @@
   CBC_DataMatrixWriter();
   ~CBC_DataMatrixWriter() override;
 
-  uint8_t* Encode(const WideString& contents,
-                  int32_t& outWidth,
-                  int32_t& outHeight);
+  std::vector<uint8_t> Encode(const WideString& contents,
+                              int32_t* pOutWidth,
+                              int32_t* pOutHeight);
 
   // CBC_TwoDimWriter
   bool SetErrorCorrectionLevel(int32_t level) override;