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

experimental/PdfViewer/SkPdfURLAliasDictionary_autogen.h

 #ifndef __DEFINED__SkPdfURLAliasDictionary
 #define __DEFINED__SkPdfURLAliasDictionary
 
 #include "SkPdfEnums_autogen.h"
 #include "SkPdfArray_autogen.h"
 #include "SkPdfDictionary_autogen.h"
 
+// Entries in a URL alias dictionary
 class SkPdfURLAliasDictionary : public SkPdfDictionary {
 public:
   virtual SkPdfObjectType getType() const { return kURLAliasDictionary_SkPdfObjectType;}
   virtual SkPdfObjectType getTypeEnd() const { return (SkPdfObjectType)(kURLAliasDictionary_SkPdfObjectType + 1);}
 public:
   virtual SkPdfURLAliasDictionary* asURLAliasDictionary() {return this;}
   virtual const SkPdfURLAliasDictionary* asURLAliasDictionary() const {return this;}
 
 private:
   virtual SkPdfALinkAnnotationDictionary* asALinkAnnotationDictionary() {return NULL;}
@@ skipping 496 matching lines @@
 
 public:
 private:
 public:
   SkPdfURLAliasDictionary(const PdfMemDocument* podofoDoc = NULL, const PdfObject* podofoObj = NULL) : SkPdfDictionary(podofoDoc, podofoObj) {}
 
   virtual bool valid() const {return true;}
 
   SkPdfURLAliasDictionary& operator=(const SkPdfURLAliasDictionary& from) {this->fPodofoDoc = from.fPodofoDoc; this->fPodofoObj = from.fPodofoObj; return *this;}
 
+/** (Required) The destination URL to which all of the chains specified by the C entry lead.
+**/
+  bool has_U() const {
+    return (ObjectFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "U", "", NULL));
+  }
+
   std::string U() const {
     std::string ret;
     if (StringFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "U", "", &ret)) return ret;
     // TODO(edisonn): warn about missing required field, assert for known good pdfs
     return "";
   }
 
+/** (Optional) An array of one or more arrays of strings, each representing a chain of URLs
+ *  leading to the common destination specified by U.
+**/
+  bool has_C() const {
+    return (ObjectFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "C", "", NULL));
+  }
+
   SkPdfArray C() const {
     SkPdfArray ret;
     if (ArrayFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "C", "", &ret)) return ret;
     // TODO(edisonn): warn about missing required field, assert for known good pdfs
     return SkPdfArray();
   }
 
 };
 
 #endif  // __DEFINED__SkPdfURLAliasDictionary