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

experimental/PdfViewer/SkPdfBasics.h

 #ifndef __DEFINED__SkPdfBasics
 #define __DEFINED__SkPdfBasics
 
 #include "SkCanvas.h"
 #include "SkPaint.h"
 #include "SkPdfConfig.h"
 
 #include <iostream>
 #include <cstdio>
 #include <map>
@@ skipping 203 matching lines @@
 soft mask         dictionary    (PDF 1.4) A soft-mask dictionary (see “Soft-Mask Dictionaries” on
                   or name       page 445) specifying the mask shape or mask opacity values to be
                                 used in the transparent imaging model (see “Source Shape and
                                 Opacity” on page 421 and “Mask Shape and Opacity” on page 443),
                                 or the name None if no such mask is specified. This parameter is
                                 implicitly reset to its initial value at the beginning of execution of a
                                 transparency group XObject (see Section 7.5.5, “Transparency
                                 Group XObjects”). Initial value: None.
  */
     SkPdfSoftMaskDictionary* fSoftMaskDictionary;
-    SkBitmap                 fSMask;
+    // TODO(edisonn): make sMask private, add setter and getter, ref/unref/..., at the moment we most likely leask
+    SkBitmap*                fSMask;
 
 
 /*
 alpha constant    number        (PDF 1.4) The constant shape or constant opacity value to be used
                                 in the transparent imaging model (see “Source Shape and Opacity”
                                 on page 421 and “Constant Shape and Opacity” on page 444).
                                 There are two separate alpha constant parameters: one for stroking
                                 and one for all other painting operations. This parameter is implic-
                                 itly reset to its initial value at the beginning of execution of a trans-
                                 parency group XObject (see Section 7.5.5, “Transparency Group
@@ skipping 152 matching lines @@
     kPartial_PdfResult,
     kNYI_PdfResult,
     kIgnoreError_PdfResult,
     kError_PdfResult,
     kUnsupported_PdfResult,
 
     kCount_PdfResult
 };
 
 #endif  // __DEFINED__SkPdfBasics