Delete SkColorSpace::gammaNamed() from public API

src/image/SkSurface_Raster.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkSurface_Base.h"
 #include "SkImagePriv.h"
 #include "SkCanvas.h"
@@ skipping 49 matching lines @@
             }
             shift = 1;
             break;
         case kN32_SkColorType:
             if (info.colorSpace() && !info.colorSpace()->gammaCloseToSRGB()) {
                 return false;
             }
             shift = 2;
             break;
         case kRGBA_F16_SkColorType:
-            if (!info.colorSpace() ||
-                SkColorSpace::kLinear_GammaNamed != info.colorSpace()->gammaNamed()) {
+            if (!info.colorSpace() || !info.colorSpace()->gammaIsLinear()) {
                 return false;
             }
             shift = 3;
             break;
         default:
             return false;
     }
 
     if (kIgnoreRowBytesValue == rowBytes) {
         return true;
@@ skipping 129 matching lines @@
 
     SkAutoTUnref<SkPixelRef> pr(SkMallocPixelRef::NewZeroed(info, rowBytes, nullptr));
     if (nullptr == pr.get()) {
         return nullptr;
     }
     if (rowBytes) {
         SkASSERT(pr->rowBytes() == rowBytes);
     }
     return sk_make_sp<SkSurface_Raster>(pr, props);
 }