[heap] Make link from optimized code to inlined code explicit.

src/crankshaft/lithium-codegen.cc

Index: src/crankshaft/lithium-codegen.cc
diff --git a/src/crankshaft/lithium-codegen.cc b/src/crankshaft/lithium-codegen.cc
index 10e06dd65d4e4865ca224094cc7f94504779723d..5bd1e6a9b872426627bc306eb5bbec9f95b64306 100644
--- a/src/crankshaft/lithium-codegen.cc
+++ b/src/crankshaft/lithium-codegen.cc
@@ -332,10 +332,17 @@ void LCodeGenBase::PopulateDeoptimizationData(Handle<Code> code) {
 
 void LCodeGenBase::PopulateDeoptimizationLiteralsWithInlinedFunctions() {
   DCHECK_EQ(0, deoptimization_literals_.length());
-  for (auto function : chunk()->inlined_functions()) {
+  for (Handle<SharedFunctionInfo> function : chunk()->inlined_functions()) {
     DefineDeoptimizationLiteral(function);
   }
   inlined_function_count_ = deoptimization_literals_.length();
+
+  // Define deoptimization literals for all unoptimized code objects of inlined
+  // functions. This ensures unoptimized code is kept alive by optimized code.
+  AllowDeferredHandleDereference allow_shared_function_info_dereference;
+  for (Handle<SharedFunctionInfo> function : chunk()->inlined_functions()) {
+    DefineDeoptimizationLiteral(handle(function->code()));
+  }
 }