Reland "Implement `dumpInfo` for .fp files."

This is a reland of a1df23c8b71e193d2facfc3c6af79626f47d4666

Original change's description:
> Implement `dumpInfo` for .fp files.
>
> Change-Id: I40f6c1a02e194f090e67a0e3f2d7d83cd2317efd
> Bug: skia:8434
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/309139
> Commit-Queue: Brian Osman <brianosman@google.com>
> Reviewed-by: Brian Osman <brianosman@google.com>
> Auto-Submit: John Stiles <johnstiles@google.com>

Bug: skia:8434
Change-Id: If485635440b800f8a282c871a1c5f2801608d3c7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/309660
Commit-Queue: John Stiles <johnstiles@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
diff --git a/src/gpu/gradients/generated/GrSweepGradientLayout.cpp b/src/gpu/gradients/generated/GrSweepGradientLayout.cpp
index 8bb3372..a661b68 100644
--- a/src/gpu/gradients/generated/GrSweepGradientLayout.cpp
+++ b/src/gpu/gradients/generated/GrSweepGradientLayout.cpp
@@ -91,6 +91,11 @@
 std::unique_ptr<GrFragmentProcessor> GrSweepGradientLayout::clone() const {
     return std::make_unique<GrSweepGradientLayout>(*this);
 }
+#ifdef SK_DEBUG
+SkString GrSweepGradientLayout::dumpInfo() const {
+    return SkStringPrintf("SweepGradientLayout(bias=%f, scale=%f)", bias, scale);
+}
+#endif
 GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrSweepGradientLayout);
 #if GR_TEST_UTILS
 std::unique_ptr<GrFragmentProcessor> GrSweepGradientLayout::TestCreate(GrProcessorTestData* d) {