Make closures optimizable by Crankshaft compiler.

src/ia32/lithium-ia32.cc

Index: src/ia32/lithium-ia32.cc
diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index 1f9714357e2f7f63c737c2e8f0b1d112ae81af9d..1cafb23d4f6118515e369bbfcec3ea5ce47098d6 100644
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -263,6 +263,11 @@ void LUnaryMathOperation::PrintDataTo(StringStream* stream) const {
 }
 
 
+void LLoadContextSlot::PrintDataTo(StringStream* stream) const {
+  hydrogen()->PrintDataTo(stream);
+}
+
+
 void LCallKeyed::PrintDataTo(StringStream* stream) const {
   stream->Add("[ecx] #%d / ", arity());
 }
@@ -1827,6 +1832,11 @@ LInstruction* LChunkBuilder::DoStoreGlobal(HStoreGlobal* instr) {
 }
 
 
+LInstruction* LChunkBuilder::DoLoadContextSlot(HLoadContextSlot* instr) {
+  return DefineAsRegister(new LLoadContextSlot);
+}
+
+
 LInstruction* LChunkBuilder::DoLoadNamedField(HLoadNamedField* instr) {
   return DefineAsRegister(
       new LLoadNamedField(UseRegisterAtStart(instr->object())));