SkPDF: allow PDF module to be disabled in DM and SampleApp

tests/PDFPrimitivesTest.cpp

 /*
  * Copyright 2010 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkData.h"
 #include "SkDocument.h"
 #include "SkFlate.h"
 #include "SkImageEncoder.h"
 #include "SkMatrix.h"
 #include "SkPDFCanon.h"
 #include "SkPDFDevice.h"
 #include "SkPDFStream.h"
 #include "SkPDFTypes.h"
 #include "SkReadBuffer.h"
 #include "SkScalar.h"
 #include "SkStream.h"
 #include "SkTypes.h"
 #include "Test.h"
 
+#if SK_SUPPORT_PDF
+
 #define DUMMY_TEXT "DCT compessed stream."
 
 namespace {
 struct Catalog {
     SkPDFSubstituteMap substitutes;
     SkPDFObjNumMap numbers;
 };
 }  // namespace
 
 template <typename T>
@@ skipping 371 matching lines @@
     // Filter just created; should be unvisited.
     REPORTER_ASSERT(reporter, !filter->visited());
     SkPaint paint;
     paint.setImageFilter(filter.get());
     canvas->drawRect(SkRect::MakeWH(100, 100), paint);
     doc->close();
 
     // Filter was used in rendering; should be visited.
     REPORTER_ASSERT(reporter, filter->visited());
 }
+#endif  // SK_SUPPORT_PDF