color: Always use parametric color spaces for raster

ui/gfx/skia_color_space_util.h

Index: ui/gfx/skia_color_space_util.h
diff --git a/ui/gfx/skia_color_space_util.h b/ui/gfx/skia_color_space_util.h
index f22b040e8848708656b917ff48ec511e61c8dc79..5ece50eca06d0dca08dbbb777b76959a8c29b625 100644
--- a/ui/gfx/skia_color_space_util.h
+++ b/ui/gfx/skia_color_space_util.h
@@ -6,6 +6,7 @@
 #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 {
@@ -29,6 +30,14 @@ bool GFX_EXPORT SkApproximateTransferFn(const float* x,
                                         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