Add flag trap_on_stub_deopt. We want to be able to trap on hydrogen stub bailouts.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index cc635100b18dcab10c9e4e9c02aee8ab50206464..ef1666f12184562f0113aa0ce0f9f2325e33ac6d 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -687,7 +687,8 @@ void LCodeGen::DeoptimizeIf(Condition cc,
 
   ASSERT(FLAG_deopt_every_n_times == 0);  // Not yet implemented on x64.
 
-  if (FLAG_trap_on_deopt && info()->IsOptimizing()) {
+  if ((FLAG_trap_on_deopt && info()->IsOptimizing()) ||
+      (FLAG_trap_on_stub_deopt && info()->IsStub())) {
     Label done;
     if (cc != no_condition) {
       __ j(NegateCondition(cc), &done, Label::kNear);