Deal with ca and CA transparency operators in pdf. add comments to generated classes.

experimental/PdfViewer/SkPdfFDFTrailerDictionary_autogen.h

 #ifndef __DEFINED__SkPdfFDFTrailerDictionary
 #define __DEFINED__SkPdfFDFTrailerDictionary
 
 #include "SkPdfEnums_autogen.h"
 #include "SkPdfArray_autogen.h"
 #include "SkPdfDictionary_autogen.h"
 
+// Entry in the FDF trailer dictionary
 class SkPdfFDFTrailerDictionary : public SkPdfDictionary {
 public:
   virtual SkPdfObjectType getType() const { return kFDFTrailerDictionary_SkPdfObjectType;}
   virtual SkPdfObjectType getTypeEnd() const { return (SkPdfObjectType)(kFDFTrailerDictionary_SkPdfObjectType + 1);}
 public:
   virtual SkPdfFDFTrailerDictionary* asFDFTrailerDictionary() {return this;}
   virtual const SkPdfFDFTrailerDictionary* asFDFTrailerDictionary() const {return this;}
 
 private:
   virtual SkPdfALinkAnnotationDictionary* asALinkAnnotationDictionary() {return NULL;}
@@ skipping 496 matching lines @@
 
 public:
 private:
 public:
   SkPdfFDFTrailerDictionary(const PdfMemDocument* podofoDoc = NULL, const PdfObject* podofoObj = NULL) : SkPdfDictionary(podofoDoc, podofoObj) {}
 
   virtual bool valid() const {return true;}
 
   SkPdfFDFTrailerDictionary& operator=(const SkPdfFDFTrailerDictionary& from) {this->fPodofoDoc = from.fPodofoDoc; this->fPodofoObj = from.fPodofoObj; return *this;}
 
+/** (Required; must be an indirect reference) The catalog object for this FDF file (see
+ *  "FDF Catalog," below).
+**/
+  bool has_Root() const {
+    return (ObjectFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "Root", "", NULL));
+  }
+
   SkPdfDictionary* Root() const {
     SkPdfDictionary* ret;
     if (DictionaryFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "Root", "", &ret)) return ret;
     // TODO(edisonn): warn about missing required field, assert for known good pdfs
     return NULL;
   }
 
 };
 
 #endif  // __DEFINED__SkPdfFDFTrailerDictionary