[turbofan] Add initial support for SOFT deopts.

src/compiler/js-native-context-specialization.cc

Index: src/compiler/js-native-context-specialization.cc
diff --git a/src/compiler/js-native-context-specialization.cc b/src/compiler/js-native-context-specialization.cc
index d6c4fa9ab5809a95f266c9def4a7e1683bbe76f0..b1fadb5ae252b7dc8e2a310c4d2b7b4aa57539ce 100644
--- a/src/compiler/js-native-context-specialization.cc
+++ b/src/compiler/js-native-context-specialization.cc
@@ -411,8 +411,9 @@ Reduction JSNativeContextSpecialization::ReduceNamedAccess(
           ? exit_controls.front()
           : graph()->NewNode(common()->Merge(exit_control_count),
                              exit_control_count, &exit_controls.front());
-  Node* deoptimize = graph()->NewNode(common()->Deoptimize(), frame_state,
-                                      exit_effect, exit_control);
+  Node* deoptimize =
+      graph()->NewNode(common()->Deoptimize(DeoptimizeKind::kEager),
+                       frame_state, exit_effect, exit_control);
   // TODO(bmeurer): This should be on the AdvancedReducer somehow.
   NodeProperties::MergeControlToEnd(graph(), common(), deoptimize);
 
@@ -838,8 +839,9 @@ Reduction JSNativeContextSpecialization::ReduceElementAccess(
           ? exit_controls.front()
           : graph()->NewNode(common()->Merge(exit_control_count),
                              exit_control_count, &exit_controls.front());
-  Node* deoptimize = graph()->NewNode(common()->Deoptimize(), frame_state,
-                                      exit_effect, exit_control);
+  Node* deoptimize =
+      graph()->NewNode(common()->Deoptimize(DeoptimizeKind::kEager),
+                       frame_state, exit_effect, exit_control);
   // TODO(bmeurer): This should be on the AdvancedReducer somehow.
   NodeProperties::MergeControlToEnd(graph(), common(), deoptimize);