pdfviewer: add indexed rbg image support, enhanche caching(setData) for SkPdfObject

experimental/PdfViewer/pdfparser/native/SkPdfObject.cpp

 
 #include "SkPdfObject.h"
 #include "SkPdfStreamCommonDictionary_autogen.h"
 
 #include "SkFlate.h"
 #include "SkStream.h"
 #include "SkPdfNativeTokenizer.h"
 
+#include "SkBitmap.h"
+#include "SkPdfFont.h"
+
 SkPdfObject SkPdfObject::kNull = SkPdfObject::makeNull();
 
 bool SkPdfObject::applyFlateDecodeFilter() {
     if (!SkFlate::HaveFlate()) {
         // TODO(edisonn): warn, make callers handle it
         return false;
     }
 
     const unsigned char* old = fStr.fBuffer;
     bool deleteOld = isStreamOwned();
@@ skipping 60 matching lines @@
                     break;
                 }
             } else {
                 // TODO(edisonn): report warning
             }
         }
     }
 
     return true;
 }
+
+void SkPdfObject::releaseData() {
+    if (fData) {
+        switch (fDataType) {
+            case kFont_Data:
+                delete (SkPdfFont*)fData;
+                break;
+            case kBitmap_Data:
+                delete (SkBitmap*)fData;
+                break;
+            default:
+                SkASSERT(false);
+                break;
+        }
+    }
+    fData = NULL;
+    fDataType = kEmpty_Data;
+}