[heap] Perform more embedder tracing in incremental marking step

This should fix GC latency regressions introduced in 4c6598.

Bug: chromium:926189, chromium:930844, chromium:930693,chromium:931629
Change-Id: I81c91829badbeea82d6e44670d07794632869424
Reviewed-on: https://chromium-review.googlesource.com/c/1477216Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59668}

src/heap/incremental-marking.cc

@@ -996,14 +996,16 @@ StepResult IncrementalMarking::AdvanceWithDeadline(
   double remaining_time_in_ms = 0.0;
   StepResult result;
   do {
-    StepResult embedder_result = EmbedderStep(kStepSizeInMs / 2);
     StepResult v8_result =
         V8Step(kStepSizeInMs / 2, completion_action, step_origin);
+    remaining_time_in_ms =
+        deadline_in_ms - heap()->MonotonicallyIncreasingTimeInMs();
+    StepResult embedder_result =
+        EmbedderStep(Min(kStepSizeInMs, remaining_time_in_ms));
     result = CombineStepResults(v8_result, embedder_result);
     remaining_time_in_ms =
         deadline_in_ms - heap()->MonotonicallyIncreasingTimeInMs();
-  } while (remaining_time_in_ms > kStepSizeInMs && !IsComplete() &&
-           !marking_worklist()->IsEmpty() &&
+  } while (remaining_time_in_ms >= kStepSizeInMs &&
            result == StepResult::kMoreWorkRemaining);
   return result;
 }