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, 3 insertions, 2 deletions

diff --git a/xfa/fxbarcode/BC_TwoDimWriter.h b/xfa/fxbarcode/BC_TwoDimWriter.h
index 625680413d..da2e6d9c4d 100644
--- a/xfa/fxbarcode/BC_TwoDimWriter.h
+++ b/xfa/fxbarcode/BC_TwoDimWriter.h
@@ -15,7 +15,8 @@ class CFX_RenderDevice;
 class CBC_TwoDimWriter : public CBC_Writer {
  public:
   CBC_TwoDimWriter();
-  virtual ~CBC_TwoDimWriter();
+  ~CBC_TwoDimWriter() override;
+
   virtual void RenderResult(uint8_t* code,
                             int32_t codeWidth,
                             int32_t codeHeight,
@@ -24,7 +25,7 @@ class CBC_TwoDimWriter : public CBC_Writer {
   virtual void RenderDeviceResult(CFX_RenderDevice* device,
                                   const CFX_Matrix* matrix);
   virtual FX_BOOL SetErrorCorrectionLevel(int32_t level) = 0;
-  virtual int32_t GetErrorCorrectionLevel() { return m_iCorrectLevel; }
+  virtual int32_t GetErrorCorrectionLevel();
 
  protected:
   int32_t m_iCorrectLevel;