Move SkPdfContext into its own files.

experimental/PdfViewer/SkPdfGraphicsState.cpp

Index: experimental/PdfViewer/SkPdfGraphicsState.cpp
diff --git a/experimental/PdfViewer/SkPdfGraphicsState.cpp b/experimental/PdfViewer/SkPdfGraphicsState.cpp
index 2a01b14b90991a70045285827c09ab1ccfae59ae..b52f22ccc71c340e2e880eec2a6500b4798aedb8 100644
--- a/experimental/PdfViewer/SkPdfGraphicsState.cpp
+++ b/experimental/PdfViewer/SkPdfGraphicsState.cpp
@@ -8,16 +8,6 @@
 #include "SkPdfGraphicsState.h"
 
 #include "SkDashPathEffect.h"
-#include "SkPdfNativeTokenizer.h"
-
-SkPdfContext::SkPdfContext(SkPdfNativeDoc* doc)
-    : fPdfDoc(doc)
-    , fTmpPageAllocator(new SkPdfAllocator()) {
-}
-
-SkPdfContext::~SkPdfContext() {
-    delete fTmpPageAllocator;
-}
 
 void SkPdfGraphicsState::applyGraphicsState(SkPaint* paint, bool stroking) {
     if (stroking) {