Regres: Adjust test transition rules for CI reporting

Not passing does not equal failing, and not failing does not equal passing, as there's the muddy waters of UNSUPPORTED and friends.

Check for transitions of [not failing -> failing] and [not passing -> passing] as reasons to say something.

Bug: b/137671242
Change-Id: Ibb612531da494738c411a1b3f1ac40a5c5078fdc
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/34188
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Ben Clayton <bclayton@google.com>
diff --git a/tests/regres/main.go b/tests/regres/main.go
index 0549874..fcfeea7 100644
--- a/tests/regres/main.go
+++ b/tests/regres/main.go
@@ -993,9 +993,9 @@
 			continue
 		}
 		switch {
-		case old.Status.Passing() && new.Status.Failing():
+		case !old.Status.Failing() && new.Status.Failing():
 			broken = append(broken, test)
-		case old.Status.Failing() && new.Status.Passing():
+		case !old.Status.Passing() && new.Status.Passing():
 			fixed = append(fixed, test)
 		case old.Status != new.Status:
 			changed = append(changed, test)