[vm] Don't assert assuming FLAG_max_polymorphic_checks is the same between AppJIT training and execution.

Compare FLAG_optimization_counter_threshold, which can likewise change; optimized compilation might happen sooner or later than with a consistent flag value, but should still be correct.

TEST=dartfuzz
Bug: https://github.com/dart-lang/sdk/issues/55625
Change-Id: Iced616163ecf8b3d0a811c67e0c01a9be3d8b18b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/365904
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index 8c6c314..d2258ed 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -17501,9 +17501,6 @@
   result.SetDeoptReasons(from.DeoptReasons());
   result.set_is_megamorphic(is_megamorphic);
 
-  RELEASE_ASSERT(!is_megamorphic ||
-                 result.NumberOfChecks() >= FLAG_max_polymorphic_checks);
-
   DEBUG_ONLY(result.AssertInvariantsAreSatisfied());
 
   return result.ptr();