Add SkPDFResourceDict class, refactor existing code

src/pdf/SkPDFPage.cpp

Index: src/pdf/SkPDFPage.cpp
diff --git a/src/pdf/SkPDFPage.cpp b/src/pdf/SkPDFPage.cpp
index 414c521210f3fd378f247d75be19d031b22046f1..4d244eec183c34536421701b27ff20cfaf721c13 100644
--- a/src/pdf/SkPDFPage.cpp
+++ b/src/pdf/SkPDFPage.cpp
@@ -11,6 +11,7 @@
 #include "SkPDFCatalog.h"
 #include "SkPDFDevice.h"
 #include "SkPDFPage.h"
+#include "SkPDFResourceDict.h"
 #include "SkStream.h"
 
 SkPDFPage::SkPDFPage(SkPDFDevice* content)
@@ -24,8 +25,9 @@ SkPDFPage::~SkPDFPage() {}
 void SkPDFPage::finalizePage(SkPDFCatalog* catalog, bool firstPage,
                              const SkTSet<SkPDFObject*>& knownResourceObjects,
                              SkTSet<SkPDFObject*>* newResourceObjects) {
+    SkPDFResourceDict* resourceDict = fDevice->getResourceDict();
     if (fContentStream.get() == NULL) {
-        insert("Resources", fDevice->getResourceDict());
+        insert("Resources", resourceDict);
         SkSafeUnref(this->insert("MediaBox", fDevice->copyMediaBox()));
         if (!SkToBool(catalog->getDocumentFlags() &
                       SkPDFDocument::kNoLinks_Flags)) {
@@ -40,7 +42,7 @@ void SkPDFPage::finalizePage(SkPDFCatalog* catalog, bool firstPage,
         insert("Contents", new SkPDFObjRef(fContentStream.get()))->unref();
     }
     catalog->addObject(fContentStream.get(), firstPage);
-    fDevice->getResources(knownResourceObjects, newResourceObjects, true);
+    resourceDict->getResources(knownResourceObjects, newResourceObjects, true);
 }
 
 off_t SkPDFPage::getPageSize(SkPDFCatalog* catalog, off_t fileOffset) {