[heap] Clear cached wrappers upon aborting incremental marking

BUG=chromium:468240,chromium:668060

Review-Url: https://codereview.chromium.org/2551973005
Cr-Commit-Position: refs/heads/master@{#41553}

src/heap/heap.h

@@ -1224,6 +1224,7 @@ class Heap {
   EmbedderHeapTracer* embedder_heap_tracer() { return embedder_heap_tracer_; }
 
   size_t wrappers_to_trace() { return wrappers_to_trace_.size(); }
+  void clear_wrappers_to_trace() { wrappers_to_trace_.clear(); }
 
   // ===========================================================================
   // External string table API. ================================================

src/heap/mark-compact.cc

@@ -800,6 +800,7 @@ void MarkCompactCollector::Prepare() {
     AbortCompaction();
     if (heap_->UsingEmbedderHeapTracer()) {
       heap_->embedder_heap_tracer()->AbortTracing();
+      heap_->clear_wrappers_to_trace();
     }
     marking_deque()->Clear();
     was_marked_incrementally_ = false;