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

experimental/PdfViewer/SkPdfURIDictionary_autogen.h

 #ifndef __DEFINED__SkPdfURIDictionary
 #define __DEFINED__SkPdfURIDictionary
 
 #include "SkPdfEnums_autogen.h"
 #include "SkPdfArray_autogen.h"
 #include "SkPdfDictionary_autogen.h"
 
+// Entry in a URI dictionary
 class SkPdfURIDictionary : public SkPdfDictionary {
 public:
   virtual SkPdfObjectType getType() const { return kURIDictionary_SkPdfObjectType;}
   virtual SkPdfObjectType getTypeEnd() const { return (SkPdfObjectType)(kURIDictionary_SkPdfObjectType + 1);}
 public:
   virtual SkPdfURIDictionary* asURIDictionary() {return this;}
   virtual const SkPdfURIDictionary* asURIDictionary() const {return this;}
 
 private:
   virtual SkPdfALinkAnnotationDictionary* asALinkAnnotationDictionary() {return NULL;}
@@ skipping 496 matching lines @@
 
 public:
 private:
 public:
   SkPdfURIDictionary(const PdfMemDocument* podofoDoc = NULL, const PdfObject* podofoObj = NULL) : SkPdfDictionary(podofoDoc, podofoObj) {}
 
   virtual bool valid() const {return true;}
 
   SkPdfURIDictionary& operator=(const SkPdfURIDictionary& from) {this->fPodofoDoc = from.fPodofoDoc; this->fPodofoObj = from.fPodofoObj; return *this;}
 
+/** (Optional) The base URI to be used in resolving relative URI references. URI actions
+ *  within the document may specify URIs in partial form, to be interpreted relative to
+ *  this base address. If no base URI is specified, such partial URIs will be interpreted rel-
+ *  ative to the location of the document itself. The use of this entry is parallel to that of
+ *  the body element <BASE>, as described in section 2.7.2 of Internet RFC 1866, Hyper-
+ *  text Markup Language 2.0 Proposed Standard (see the Bibliography).
+**/
+  bool has_Base() const {
+    return (ObjectFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "Base", "", NULL));
+  }
+
   std::string Base() const {
     std::string ret;
     if (StringFromDictionary(fPodofoDoc, fPodofoObj->GetDictionary(), "Base", "", &ret)) return ret;
     // TODO(edisonn): warn about missing required field, assert for known good pdfs
     return "";
   }
 
 };
 
 #endif  // __DEFINED__SkPdfURIDictionary