Update simple gradient functions to use only a single return.

By avoiding the introduction of a temporary variable, they can remain
candidates for inlining even after we pare back the inliner logic.
More info: http://go/optimization-in-sksl-inliner

Change-Id: If58c757b8754036b0b0530379b639c09953744ea
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/384859
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
diff --git a/src/gpu/gradients/generated/GrLinearGradientLayout.cpp b/src/gpu/gradients/generated/GrLinearGradientLayout.cpp
index 09a3b92..98e576f 100644
--- a/src/gpu/gradients/generated/GrLinearGradientLayout.cpp
+++ b/src/gpu/gradients/generated/GrLinearGradientLayout.cpp
@@ -25,8 +25,7 @@
         const GrLinearGradientLayout& _outer = args.fFp.cast<GrLinearGradientLayout>();
         (void)_outer;
         fragBuilder->codeAppendf(
-                R"SkSL(half t = half(%s.x) + 9.9999997473787516e-06;
-return half4(t, 1.0, 0.0, 0.0);
+                R"SkSL(return half4(half(%s.x) + 9.9999997473787516e-06, 1.0, 0.0, 0.0);
 )SkSL",
                 args.fSampleCoord);
     }