Store SkColorSpaceXform gamma LUTs in a malloced field

src/core/SkColorSpaceXform.h

Index: src/core/SkColorSpaceXform.h
diff --git a/src/core/SkColorSpaceXform.h b/src/core/SkColorSpaceXform.h
index 6d63879653a4a1a72ceb2d741a3f69bd22d91a8a..c80cd15dcae4f24e335a4e4d1e44f831cdb00a2e 100644
--- a/src/core/SkColorSpaceXform.h
+++ b/src/core/SkColorSpaceXform.h
@@ -77,16 +77,13 @@ private:
 
     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);
 };