A flush and submit apis to public headers.

We add a new flushAndSubmit() to replace the current flush() call. In
the future all other flush(GrFlushInfo) type calls will not do a
submission of work to the GPU. Instead an explicit submit call will have
to be made. flushAndSubmit will do a flush and submit.

Also adds a no-op submit call. This allows us to stage the flush submit
changes by updating all clients that use non simple flushes to add
a submit call immediately after each flush. Then we can change the logic
of where the submission happens from flush to submit without breaking
folks.

Bug: skia:10118
Change-Id: I4f02189a21912d52b888597c7734b4ca0baee792
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/289478
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/RELEASE_NOTES.txt b/RELEASE_NOTES.txt
index 5376549..3b8386b 100644
--- a/RELEASE_NOTES.txt
+++ b/RELEASE_NOTES.txt
@@ -5,6 +5,9 @@
 * * *
 
 Milestone 84
+  * Deprecate GrContext and SkSurface flush() call and replace ith with flushAndSubmit().
+    This only effects the default flush call that takes no parameters.
+    https://review.skia.org/289478
 
   * GrContext::createBackendTexture functions that initialize the texture no longer
     guarantee that all the data has been uploaded and the gpu is done with the texture.