[turbofan] reenable escape analysis to further investigate crashes

src/compiler/escape-analysis.cc

Index: src/compiler/escape-analysis.cc
diff --git a/src/compiler/escape-analysis.cc b/src/compiler/escape-analysis.cc
index 95c06797603ead1144f785e2f87d592fee3dc08a..a61d90ebaffaf420badacca655bef582d9e2d1a9 100644
--- a/src/compiler/escape-analysis.cc
+++ b/src/compiler/escape-analysis.cc
@@ -441,6 +441,15 @@ bool VirtualObject::MergeFields(size_t i, Node* at, MergeCache* cache,
   Node* rep = GetField(i);
   if (!rep || !IsCreatedPhi(i)) {
     Node* control = NodeProperties::GetControlInput(at);
+
+    // Check to debug canary.
+    CHECK_NOT_NULL(control);
+    CHECK(!control->IsDead());
+    for (Node* input : cache->fields()) {
+      CHECK_NOT_NULL(input);
+      CHECK(!input->IsDead());
+    }
+
     cache->fields().push_back(control);
     Node* phi = graph->NewNode(
         common->Phi(MachineRepresentation::kTagged, value_input_count),