Fix assert in GetOverlayRect when transforming video with Ozone overlay

cc/output/overlay_candidate_validator.h

Index: cc/output/overlay_candidate_validator.h
diff --git a/cc/output/overlay_candidate_validator.h b/cc/output/overlay_candidate_validator.h
index 036eafc4d1f24e437c1fed508f2e68da998c555c..60647316f8b56b6f2944710142d17ec86b996ac5 100644
--- a/cc/output/overlay_candidate_validator.h
+++ b/cc/output/overlay_candidate_validator.h
@@ -19,7 +19,9 @@ class CC_EXPORT OverlayCandidateValidator {
   // A list of possible overlay candidates is presented to this function.
   // The expected result is that those candidates that can be in a separate
   // plane are marked with |overlay_handled| set to true, otherwise they are
-  // to be traditionally composited.
+  // to be traditionally composited. Candidates with |overlay_handled| set to
+  // true must also have their |display_rect| converted to integer
+  // coordinates if necessary.
   virtual void CheckOverlaySupport(OverlayCandidateList* surfaces) = 0;
 
   virtual ~OverlayCandidateValidator() {}