SkVertices: Remove volatile/nonvolatile bit

No one was using this, and it added significant complexity to
GrDrawVerticesOp.

Bug: skia:9984
Change-Id: I23f38b3f5d853a8e531f13b6931cd57b5985a2c8
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/276407
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
diff --git a/RELEASE_NOTES.txt b/RELEASE_NOTES.txt
index 9b7dddc..773e78f 100644
--- a/RELEASE_NOTES.txt
+++ b/RELEASE_NOTES.txt
@@ -7,6 +7,9 @@
 Milestone 82
 
 <Insert new notes here- top is most recent.>
+  * Removed "volatile" flag from SkVertices. All SkVertices objects are assumed to be
+    volatile (the previous default behavior).
+
   * Make it possible to selectively turn on/off individual encoders/decoders,
     using skia_use_(libpng/libjpeg_turbo/libwebp)(decode/encode).