Remove unnecessary includes in src/pdf/

src/pdf/SkPDFDevice.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPDFDevice_DEFINED
 #define SkPDFDevice_DEFINED
 
 #include "SkBitmap.h"
-#include "SkBitmapKey.h"
 #include "SkCanvas.h"
 #include "SkClipStack.h"
 #include "SkData.h"
 #include "SkDevice.h"
 #include "SkPaint.h"
-#include "SkPath.h"
-#include "SkPicture.h"
 #include "SkRect.h"
 #include "SkRefCnt.h"
 #include "SkStream.h"
 #include "SkTDArray.h"
-#include "SkTemplates.h"
 
 #include "SkSinglyLinkedList.h"
 
+class SkImageBitmap;
+class SkPath;
 class SkPDFArray;
 class SkPDFCanon;
 class SkPDFDevice;
 class SkPDFDocument;
 class SkPDFDict;
 class SkPDFFont;
 class SkPDFFormXObject;
 class SkPDFGlyphSetMap;
-class SkPDFGraphicState;
 class SkPDFObject;
-class SkPDFShader;
-class SkPDFStream;
 class SkRRect;
 
 /** \class SkPDFDevice
 
     The drawing context for the PDF backend.
 */
 class SkPDFDevice final : public SkBaseDevice {
 public:
     /** Create a PDF drawing context.  SkPDFDevice applies a
      *  scale-and-translate transform to move the origin from the
@@ skipping 291 matching lines @@
 
     typedef SkBaseDevice INHERITED;
 
     // TODO(edisonn): Only SkDocument_PDF and SkPDFImageShader should be able to create
     // an SkPDFDevice
     //friend class SkDocument_PDF;
     //friend class SkPDFImageShader;
 };
 
 #endif