Make code compile with clang_use_chrome_plugin (part III)

This change contains files in xfa/fxbarcode directory.
This is part of the efforts to make PDFium code compilable
by Clang chromium style plugins.

The changes are mainly the following:
-- move inline constructor/destructor of complex class/struct out-of-line;
-- add constructor/destructor of complex class/struct if not
 explicitly defined;
-- add explicit out-of-line copy constructor when needed;
-- move inline virtual functions out-of-line;
-- Properly mark virtual functions with 'override';
-- some minor cleanups;

BUG=pdfium:469

Review-Url: https://codereview.chromium.org/2067903002

1 files changed, 7 insertions, 5 deletions

diff --git a/xfa/fxbarcode/datamatrix/BC_X12Encoder.h b/xfa/fxbarcode/datamatrix/BC_X12Encoder.h
index 5dccbb1d6f..52239ce529 100644
--- a/xfa/fxbarcode/datamatrix/BC_X12Encoder.h
+++ b/xfa/fxbarcode/datamatrix/BC_X12Encoder.h
@@ -12,13 +12,15 @@ class CBC_X12Encoder;
 class CBC_X12Encoder : public CBC_C40Encoder {
  public:
   CBC_X12Encoder();
-  virtual ~CBC_X12Encoder();
-  int32_t getEncodingMode();
-  void Encode(CBC_EncoderContext& context, int32_t& e);
+  ~CBC_X12Encoder() override;
+
+  // CBC_C40Encoder
+  int32_t getEncodingMode() override;
+  void Encode(CBC_EncoderContext& context, int32_t& e) override;
   void handleEOD(CBC_EncoderContext& context,
                  CFX_WideString& buffer,
-                 int32_t& e);
-  int32_t encodeChar(FX_WCHAR c, CFX_WideString& sb, int32_t& e);
+                 int32_t& e) override;
+  int32_t encodeChar(FX_WCHAR c, CFX_WideString& sb, int32_t& e) override;
 };
 
 #endif  // XFA_FXBARCODE_DATAMATRIX_BC_X12ENCODER_H_