pdf viewer: refactor and fix a bug (SkPdfobject should not reset on destruct)

experimental/PdfViewer/SkPdfParser.h

-/*
- * Copyright 2013 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-
-#ifndef SkPdfParser_DEFINED
-#define SkPdfParser_DEFINED
-
-#include "SkPdfBasics.h"
-#include "SkPdfNativeTokenizer.h"
-
-extern "C" PdfContext* gPdfContext;
-extern "C" SkBitmap* gDumpBitmap;
-extern "C" SkCanvas* gDumpCanvas;
-
-// TODO(edisonn): Document PdfTokenLooper and subclasses.
-class PdfTokenLooper {
-protected:
-    PdfTokenLooper* fParent;
-    SkPdfNativeTokenizer* fTokenizer;
-    PdfContext* fPdfContext;
-    SkCanvas* fCanvas;
-
-public:
-    PdfTokenLooper(PdfTokenLooper* parent,
-                   SkPdfNativeTokenizer* tokenizer,
-                   PdfContext* pdfContext,
-                   SkCanvas* canvas)
-        : fParent(parent), fTokenizer(tokenizer), fPdfContext(pdfContext), fCanvas(canvas) {}
-
-    virtual ~PdfTokenLooper() {}
-
-    virtual PdfResult consumeToken(PdfToken& token) = 0;
-    virtual void loop() = 0;
-
-    void setUp(PdfTokenLooper* parent) {
-        fParent = parent;
-        fTokenizer = parent->fTokenizer;
-        fPdfContext = parent->fPdfContext;
-        fCanvas = parent->fCanvas;
-    }
-};
-
-class PdfMainLooper : public PdfTokenLooper {
-public:
-    PdfMainLooper(PdfTokenLooper* parent,
-                  SkPdfNativeTokenizer* tokenizer,
-                  PdfContext* pdfContext,
-                  SkCanvas* canvas)
-        : PdfTokenLooper(parent, tokenizer, pdfContext, canvas) {}
-
-    virtual PdfResult consumeToken(PdfToken& token);
-    virtual void loop();
-};
-
-class PdfInlineImageLooper : public PdfTokenLooper {
-public:
-    PdfInlineImageLooper()
-        : PdfTokenLooper(NULL, NULL, NULL, NULL) {}
-
-    virtual PdfResult consumeToken(PdfToken& token);
-    virtual void loop();
-    PdfResult done();
-};
-
-class PdfCompatibilitySectionLooper : public PdfTokenLooper {
-public:
-    PdfCompatibilitySectionLooper()
-        : PdfTokenLooper(NULL, NULL, NULL, NULL) {}
-
-    virtual PdfResult consumeToken(PdfToken& token);
-    virtual void loop();
-};
-
-// TODO(edisonn): move in another file
-class SkPdfViewer : public SkRefCnt {
-public:
-
-  bool load(const SkString inputFileName, SkPicture* out);
-  bool write(void*) const { return false; }
-};
-
-void reportPdfRenderStats();
-
-#endif  // SkPdfParser_DEFINED