color: Always use parametric color spaces for raster

ui/gfx/icc_profile.h

 // Copyright 2016 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_ICC_PROFILE_H_
 #define UI_GFX_ICC_PROFILE_H_
 
 #include <stdint.h>
 #include <vector>
 
@@ skipping 39 matching lines @@
 #endif
 
   // This will recover a ICCProfile from a compact ColorSpace representation.
   // Internally, this will make an effort to create an identical ICCProfile
   // to the one that created |color_space|, but this is not guaranteed.
   static ICCProfile FromColorSpace(const gfx::ColorSpace& color_space);
 
   // Create directly from profile data.
   static ICCProfile FromData(const void* icc_profile, size_t size);
 
-  // This will perform a potentially-lossy conversion to a more compact color
-  // space representation.
+  // Return a ColorSpace that references this ICCProfile. ColorTransforms
+  // created using this ColorSpace will match this ICCProfile precisely.
   const ColorSpace& GetColorSpace() const;
 
+  // Return a ColorSpace that is the best parametric approximation of this
+  // ICCProfile. The resulting ColorSpace will reference this ICCProfile only
+  // if the parametric approximation is almost exact.
+  const ColorSpace& GetParametricColorSpace() const;
+
   const std::vector<char>& GetData() const;
 
 #if defined(OS_WIN)
   // This will read monitor ICC profiles from disk and cache the results for the
   // other functions to read. This should not be called on the UI or IO thread.
   static void UpdateCachedProfilesOnBackgroundThread();
   static bool CachedProfilesNeedUpdate();
 #endif
 
  private:
   friend ICCProfile ICCProfileForTestingAdobeRGB();
   friend ICCProfile ICCProfileForTestingColorSpin();
   friend ICCProfile ICCProfileForTestingGenericRGB();
   friend ICCProfile ICCProfileForTestingSRGB();
   friend ICCProfile ICCProfileForTestingNoAnalyticTrFn();
+  friend ICCProfile ICCProfileForTestingA2BOnly();
   static const uint64_t test_id_adobe_rgb_;
   static const uint64_t test_id_color_spin_;
   static const uint64_t test_id_generic_rgb_;
   static const uint64_t test_id_srgb_;
   static const uint64_t test_id_no_analytic_tr_fn_;
+  static const uint64_t test_id_a2b_only_;
 
   // Populate |icc_profile| with the ICCProfile corresponding to id |id|. Return
-  // false if |id| is not in the cache. If |only_if_needed| is true, then return
-  // false if |color_space_is_accurate_| is true for this profile (that is, if
-  // the ICCProfile is needed to know the space precisely).
-  static bool FromId(uint64_t id, bool only_if_needed, ICCProfile* icc_profile);
+  // false if |id| is not in the cache.
+  static bool FromId(uint64_t id, ICCProfile* icc_profile);
 
   // This method is used to hard-code the |id_| to a specific value, and is
   // used by test methods to ensure that they don't conflict with the values
   // generated in the browser.
   static ICCProfile FromDataWithId(const void* icc_profile,
                                    size_t size,
                                    uint64_t id);
 
-  static bool IsValidProfileLength(size_t length);
   void ComputeColorSpaceAndCache();
 
   // This globally identifies this ICC profile. It is used to look up this ICC
   // profile from a ColorSpace object created from it. The object is invalid if
   // |id_| is zero.
   uint64_t id_ = 0;
   std::vector<char> data_;
 
+  // |color_space| always links back to this ICC profile, and its SkColorSpace
+  // is always equal to the SkColorSpace created from this ICCProfile.
   gfx::ColorSpace color_space_;
 
-  // True if |color_space_| accurately represents this color space (this is
-  // false e.g, for lookup-based profiles).
-  bool color_space_is_accurate_ = false;
+  // |parametric_color_space_| will only link back to this ICC profile if it
+  // is accurate, and its SkColorSpace will always be parametrically created.
+  gfx::ColorSpace parametric_color_space_;
 
   // This is set to true if SkICC successfully parsed this profile.
   bool successfully_parsed_by_sk_icc_ = false;
 
   FRIEND_TEST_ALL_PREFIXES(SimpleColorSpace, BT709toSRGBICC);
   FRIEND_TEST_ALL_PREFIXES(SimpleColorSpace, GetColorSpace);
   friend int ::LLVMFuzzerTestOneInput(const uint8_t*, size_t);
   friend class ColorSpace;
   friend class ColorTransformInternal;
   friend struct IPC::ParamTraits<gfx::ICCProfile>;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_ICC_PROFILE_H_