Switch SkPDFStream's internal storage from SkStream to SkData

gyp/core.gypi

 # Include this gypi to include all 'core' files
 # The parent gyp/gypi file must define
 #       'skia_src_path'     e.g. skia/trunk/src
 #       'skia_include_path' e.g. skia/trunk/include
 #
 # The skia build defines these in common_variables.gypi
 #
 {
     'sources': [
         '<(skia_src_path)/core/SkAAClip.cpp',
@@ skipping 163 matching lines @@
         '<(skia_src_path)/core/SkScan_Antihair.cpp',
         '<(skia_src_path)/core/SkScan_Hairline.cpp',
         '<(skia_src_path)/core/SkScan_Path.cpp',
         '<(skia_src_path)/core/SkShader.cpp',
         '<(skia_src_path)/core/SkSpriteBlitter_ARGB32.cpp',
         '<(skia_src_path)/core/SkSpriteBlitter_RGB16.cpp',
         '<(skia_src_path)/core/SkSinTable.h',
         '<(skia_src_path)/core/SkSpriteBlitter.h',
         '<(skia_src_path)/core/SkSpriteBlitterTemplate.h',
         '<(skia_src_path)/core/SkStream.cpp',
+        '<(skia_src_path)/core/SkStreamPriv.h',
         '<(skia_src_path)/core/SkString.cpp',
         '<(skia_src_path)/core/SkStringUtils.cpp',
         '<(skia_src_path)/core/SkStroke.h',
         '<(skia_src_path)/core/SkStroke.cpp',
         '<(skia_src_path)/core/SkStrokeRec.cpp',
         '<(skia_src_path)/core/SkStrokerPriv.cpp',
         '<(skia_src_path)/core/SkStrokerPriv.h',
         '<(skia_src_path)/core/SkTextFormatParams.h',
         '<(skia_src_path)/core/SkTextMapStateProc.h',
         '<(skia_src_path)/core/SkTileGrid.cpp',
@@ skipping 171 matching lines @@
         '<(skia_src_path)/pathops/SkPathOpsPoint.h',
         '<(skia_src_path)/pathops/SkPathOpsQuad.h',
         '<(skia_src_path)/pathops/SkPathOpsRect.h',
         '<(skia_src_path)/pathops/SkPathOpsTriangle.h',
         '<(skia_src_path)/pathops/SkPathOpsTypes.h',
         '<(skia_src_path)/pathops/SkPathWriter.h',
         '<(skia_src_path)/pathops/SkQuarticRoot.h',
         '<(skia_src_path)/pathops/SkReduceOrder.h',
     ],
 }