Add SkPDFResourceDict class, refactor existing code

src/pdf/SkPDFShader.cpp

Index: src/pdf/SkPDFShader.cpp
diff --git a/src/pdf/SkPDFShader.cpp b/src/pdf/SkPDFShader.cpp
index a0dffb7791fc4724ecc5a16403fc4b4b2efa6b58..65150f0a5690228f2de64c0c89acfe2f96765708 100644
--- a/src/pdf/SkPDFShader.cpp
+++ b/src/pdf/SkPDFShader.cpp
@@ -14,6 +14,7 @@
 #include "SkPDFCatalog.h"
 #include "SkPDFDevice.h"
 #include "SkPDFTypes.h"
+#include "SkPDFResourceDict.h"
 #include "SkPDFUtils.h"
 #include "SkScalar.h"
 #include "SkStream.h"
@@ -838,7 +839,8 @@ SkPDFImageShader::SkPDFImageShader(SkPDFShader::State* state) : fState(state) {
     // Put the canvas into the pattern stream (fContent).
     SkAutoTUnref<SkStream> content(pattern.content());
     setData(content.get());
-    pattern.getResources(fResources, &fResources, false);
+    SkPDFResourceDict* resourceDict = pattern.getResourceDict();
+    resourceDict->getRefResources(fResources, &fResources, false);
 
     insertName("Type", "Pattern");
     insertInt("PatternType", 1);
@@ -847,7 +849,7 @@ SkPDFImageShader::SkPDFImageShader(SkPDFShader::State* state) : fState(state) {
     insert("BBox", patternBBoxArray.get());
     insertScalar("XStep", patternBBox.width());
     insertScalar("YStep", patternBBox.height());
-    insert("Resources", pattern.getResourceDict());
+    insert("Resources", resourceDict);
     insert("Matrix", SkPDFUtils::MatrixToArray(finalMatrix))->unref();
 
     fState.get()->fImage.unlockPixels();