Don't serialize SkPictures in SkPictureShaders when in untrusted mode.

include/core/SkPicture.h

 /*
  * Copyright 2007 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.
  */
 
 #ifndef SkPicture_DEFINED
 #define SkPicture_DEFINED
 
@@ skipping 152 matching lines @@
     virtual int numSlowPaths() const = 0;
     friend struct SkPathCounter;
 
     // V35: Store SkRect (rather then width & height) in header
     // V36: Remove (obsolete) alphatype from SkColorTable
     // V37: Added shadow only option to SkDropShadowImageFilter (last version to record CLEAR)
     // V38: Added PictureResolution option to SkPictureImageFilter
     // V39: Added FilterLevel option to SkPictureImageFilter
     // V40: Remove UniqueID serialization from SkImageFilter.
     // V41: Added serialization of SkBitmapSource's filterQuality parameter
+    // V42: Added a bool to SkPictureShader serialization to indicate did-we-serialize-a-picture?
 
     // Only SKPs within the min/current picture version range (inclusive) can be read.
     static const uint32_t     MIN_PICTURE_VERSION = 35;     // Produced by Chrome M39.
-    static const uint32_t CURRENT_PICTURE_VERSION = 41;
+    static const uint32_t CURRENT_PICTURE_VERSION = 42;
 
     static_assert(MIN_PICTURE_VERSION <= 41,
                   "Remove kFontFileName and related code from SkFontDescriptor.cpp.");
 
     static bool IsValidPictInfo(const SkPictInfo& info);
     static SkPicture* Forwardport(const SkPictInfo&, const SkPictureData*);
 
     SkPictInfo createHeader() const;
     SkPictureData* backport() const;
 
     mutable uint32_t fUniqueID;
 };
 
 #endif