Store SkColorSpaceXform gamma LUTs in a malloced field

src/core/SkColorSpaceXform.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkColorSpaceXform_DEFINED
 #define SkColorSpaceXform_DEFINED
 
@@ skipping 59 matching lines @@
                SkAlphaType dstAlphaType) const override;
 
     static constexpr int      kDstGammaTableSize = 1024;
 
 private:
     SkColorSpaceXform_Base(const sk_sp<SkColorSpace>& srcSpace, const SkMatrix44& srcToDst,
                            const sk_sp<SkColorSpace>& dstSpace);
 
     sk_sp<SkColorLookUpTable> fColorLUT;
 
-    // May contain pointers into storage or pointers into precomputed tables.
+    // Contain pointers into storage or pointers into precomputed tables.
     const float*              fSrcGammaTables[3];
-    float                     fSrcGammaTableStorage[3 * 256];
+    const uint8_t*            fDstGammaTables[3];
+    SkAutoMalloc              fStorage;
 
     float                     fSrcToDst[16];
 
-    // May contain pointers into storage or pointers into precomputed tables.
-    const uint8_t*            fDstGammaTables[3];
-    uint8_t                   fDstGammaTableStorage[3 * kDstGammaTableSize];
-
     friend class SkColorSpaceXform;
     friend std::unique_ptr<SkColorSpaceXform> SlowIdentityXform(const sk_sp<SkColorSpace>& space);
 };
 
 // For testing.  Bypasses opts for when src and dst color spaces are equal.
 std::unique_ptr<SkColorSpaceXform> SlowIdentityXform(const sk_sp<SkColorSpace>& space);
 
 #endif