It is possible to try and draw to an unsupported format. Let this go.

src/effects/gradients/SkGradientShader.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Sk4fLinearGradient.h"
 #include "SkGradientShaderPriv.h"
 #include "SkHalf.h"
@@ skipping 1480 matching lines @@
 
             SkGradientShaderBase::GradientBitmapType bitmapType =
                 SkGradientShaderBase::GradientBitmapType::kLegacy;
             if (args.fGammaCorrect) {
                 // Try to use F16 if we can
                 if (args.fContext->caps()->isConfigTexturable(kRGBA_half_GrPixelConfig)) {
                     bitmapType = SkGradientShaderBase::GradientBitmapType::kHalfFloat;
                 } else if (args.fContext->caps()->isConfigTexturable(kSRGBA_8888_GrPixelConfig)) {
                     bitmapType = SkGradientShaderBase::GradientBitmapType::kSRGB;
                 } else {
-                    // This should never happen, but just fall back to legacy behavior
-                    SkDEBUGFAIL("Requesting a gamma-correct gradient FP without F16 or sRGB");
+                    // This can happen, but only if someone explicitly creates an unsupported
+                    // (eg sRGB) surface. Just fall back to legacy behavior.
                 }
             }
 
             SkBitmap bitmap;
             shader.getGradientTableBitmap(&bitmap, bitmapType);
 
             GrTextureStripAtlas::Desc desc;
             desc.fWidth  = bitmap.width();
             desc.fHeight = 32;
             desc.fRowHeight = bitmap.height();
@@ skipping 101 matching lines @@
             (*stops)[i] = stop;
             stop = i < outColors - 1 ? stop + random->nextUScalar1() * (1.f - stop) : 1.f;
         }
     }
     *tm = static_cast<SkShader::TileMode>(random->nextULessThan(SkShader::kTileModeCount));
 
     return outColors;
 }
 
 #endif