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

Squelches assert firing in gradient code on low-end Android bots.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2365703002

Review-Url: https://codereview.chromium.org/2365703002
diff --git a/src/effects/gradients/SkGradientShader.cpp b/src/effects/gradients/SkGradientShader.cpp
index 27f6136..d625d8e 100644
--- a/src/effects/gradients/SkGradientShader.cpp
+++ b/src/effects/gradients/SkGradientShader.cpp
@@ -1498,8 +1498,8 @@
                 } 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.
                 }
             }