Add NewRGB() with float gamma to SkColorSpace public API

tests/SurfaceTest.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include <functional>
 #include "SkCanvas.h"
 #include "SkColorSpace_Base.h"
@@ skipping 905 matching lines @@
 static void test_surface_creation_and_snapshot_with_color_space(
     skiatest::Reporter* reporter,
     const char* prefix,
     bool f16Support,
     std::function<sk_sp<SkSurface>(const SkImageInfo&)> surfaceMaker) {
 
     auto srgbColorSpace = SkColorSpace::NewNamed(SkColorSpace::kSRGB_Named);
     auto adobeColorSpace = SkColorSpace::NewNamed(SkColorSpace::kAdobeRGB_Named);
     SkMatrix44 srgbMatrix = as_CSB(srgbColorSpace)->toXYZD50();
     const float oddGamma[] = { 2.4f, 2.4f, 2.4f };
-    auto oddColorSpace = SkColorSpace_Base::NewRGB(oddGamma, srgbMatrix);
+    auto oddColorSpace = SkColorSpace::NewRGB(oddGamma, srgbMatrix);
     auto linearColorSpace = SkColorSpace::NewNamed(SkColorSpace::kSRGBLinear_Named);
 
     const struct {
         SkColorType         fColorType;
         sk_sp<SkColorSpace> fColorSpace;
         bool                fShouldWork;
         const char*         fDescription;
     } testConfigs[] = {
         { kN32_SkColorType,       nullptr,          true,  "N32-nullptr" },
         { kN32_SkColorType,       linearColorSpace, false, "N32-linear"  },
@@ skipping 70 matching lines @@
     };
 
     test_surface_creation_and_snapshot_with_color_space(reporter, "wrapped", f16Support,
                                                         wrappedSurfaceMaker);
 
     for (auto textureHandle : textureHandles) {
         context->getGpu()->deleteTestingOnlyBackendTexture(textureHandle);
     }
 }
 #endif