color: Always use parametric color spaces for raster

ui/gfx/skia_color_space_util.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_GFX_SKIA_COLOR_SPACE_UTIL_H_
 #define UI_GFX_SKIA_COLOR_SPACE_UTIL_H_
 
 #include "third_party/skia/include/core/SkColorSpace.h"
+#include "third_party/skia/include/core/SkICC.h"
 #include "ui/gfx/gfx_export.h"
 
 namespace gfx {
 
 float GFX_EXPORT SkTransferFnEval(const SkColorSpaceTransferFn& fn, float x);
 
 SkColorSpaceTransferFn GFX_EXPORT
 SkTransferFnInverse(const SkColorSpaceTransferFn& fn);
 
 bool GFX_EXPORT
 SkTransferFnsApproximatelyCancel(const SkColorSpaceTransferFn& a,
                                  const SkColorSpaceTransferFn& b);
 
 bool GFX_EXPORT
 SkTransferFnIsApproximatelyIdentity(const SkColorSpaceTransferFn& fn);
 
 // Approximates the |n| points in |x| and |t| by the transfer function |fn|.
 // Returns true if the approximation converged.
 bool GFX_EXPORT SkApproximateTransferFn(const float* x,
                                         const float* t,
                                         size_t n,
                                         SkColorSpaceTransferFn* fn);
 
+// Approximates |sk_icc| by the transfer function |fn|. Returns in |max_error|
+// the maximum pointwise of all color channels' transfer functions with |fn|.
+// Returns false if no approximation was possible, or no approximation
+// converged.
+bool GFX_EXPORT SkApproximateTransferFn(sk_sp<SkICC> sk_icc,
+                                        float* max_error,
+                                        SkColorSpaceTransferFn* fn);
+
 bool GFX_EXPORT SkMatrixIsApproximatelyIdentity(const SkMatrix44& m);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_SKIA_COLOR_SPACE_UTIL_H_