[turbofan] Reenable feedback for LoadNamed.

R=jarin@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1140943003

Cr-Commit-Position: refs/heads/master@{#28398}

src/compiler/js-type-feedback.cc

@@ -276,6 +276,7 @@ Reduction JSTypeFeedbackSpecializer::ReduceJSLoadProperty(Node* node) {
 
 Reduction JSTypeFeedbackSpecializer::ReduceJSStoreNamed(Node* node) {
   DCHECK(node->opcode() == IrOpcode::kJSStoreNamed);
+  if (true) return NoChange();  // TODO(titzer): storenamed is broken
   Node* frame_state_before = GetFrameStateBefore(node);
   if (frame_state_before == nullptr) return NoChange();
 

src/flag-definitions.h

@@ -385,8 +385,7 @@ DEFINE_BOOL(omit_map_checks_for_leaf_maps, true,
 DEFINE_BOOL(turbo, false, "enable TurboFan compiler")
 DEFINE_BOOL(turbo_greedy_regalloc, false, "use the greedy register allocator")
 DEFINE_IMPLICATION(turbo, turbo_deoptimization)
-// TODO(titzer): turn back on type feedback in turbo mode.
-// DEFINE_IMPLICATION(turbo, turbo_type_feedback)
+DEFINE_IMPLICATION(turbo, turbo_type_feedback)
 DEFINE_STRING(turbo_filter, "~~", "optimization filter for TurboFan compiler")
 DEFINE_BOOL(trace_turbo, false, "trace generated TurboFan IR")
 DEFINE_BOOL(trace_turbo_graph, false, "trace generated TurboFan graphs")