Remove Improved Perlin Noise

Is not used by a major client and can be implemented using runtime
effects for users who want this noise.

Bug: skia:10536
Change-Id: Iaa06e6e1406b808c7f8dc0f76621fecf2becabf5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/352057
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/RELEASE_NOTES.txt b/RELEASE_NOTES.txt
index 9ea0e58..fbb5a22 100644
--- a/RELEASE_NOTES.txt
+++ b/RELEASE_NOTES.txt
@@ -6,6 +6,9 @@
 
 Milestone 89
 ------------
+  * Removed SkPerlinNoiseShader::MakeImprovedNoise.
+    https://review.skia.org/352057
+
   * Removed deperated version of MakeFromYUVATextures. Use the version
     that takes GrYUVABackendTextures instead.
     https://review.skia.org/345174