Use override in more classes in fpdfsdk/

fpdfsdk/include/fsdk_baseform.h

Index: fpdfsdk/include/fsdk_baseform.h
diff --git a/fpdfsdk/include/fsdk_baseform.h b/fpdfsdk/include/fsdk_baseform.h
index bb3e7cd6538c9c74cb4c4bc9260aed7691ccc0f8..f99880110141e91a8bff6227fd20053b4fb30569 100644
--- a/fpdfsdk/include/fsdk_baseform.h
+++ b/fpdfsdk/include/fsdk_baseform.h
@@ -56,25 +56,21 @@ typedef struct _PDFSDK_FieldAction {
   FX_BOOL bFieldFull;        // in
   FX_BOOL bRC;               // in[out]
 } PDFSDK_FieldAction;
+
 class CPDFSDK_Widget : public CPDFSDK_Annot {
  public:
   CPDFSDK_Widget(CPDF_Annot* pAnnot,
                  CPDFSDK_PageView* pPageView,
                  CPDFSDK_InterForm* pInterForm);
-  virtual ~CPDFSDK_Widget();
-
-  virtual CFX_ByteString GetSubType() const;
+  ~CPDFSDK_Widget() override;
 
-  virtual CPDF_Action GetAAction(CPDF_AAction::AActionType eAAT);
+  // CPDFSDK_Annot
+  CFX_ByteString GetSubType() const override;
+  CPDF_Action GetAAction(CPDF_AAction::AActionType eAAT) override;
+  // define layout order to 2.

[Tom Sepez, 2015/08/14 19:59:18]

This comment, on the other hand, in useless.  WTF does 2 mean?

+  int GetLayoutOrder() const override { return 2; }
 
   int GetFieldType() const;
-  // define layout order to 2.
-  virtual int GetLayoutOrder() const { return 2; }
-  /*
-  FIELDFLAG_READONLY

[Tom Sepez, 2015/08/14 19:59:18]

I like this comment; it explains what kinds of #defines you get for the int
return on getfieldflags()

[Lei Zhang, 2015/08/14 21:23:49]

I added more documentation here.

-  FIELDFLAG_REQUIRED
-  FIELDFLAG_NOEXPORT
-  */
 
   int GetFieldFlags() const;
   int GetRotate() const;