[crankshaft] Get rid of the StoreFrameContext instruction.

src/crankshaft/s390/lithium-s390.cc

Index: src/crankshaft/s390/lithium-s390.cc
diff --git a/src/crankshaft/s390/lithium-s390.cc b/src/crankshaft/s390/lithium-s390.cc
index ee59e69834a638605df7f2b20ce4c95b27b93d07..8d0481f2a60fa4a58785096ec0ae5e987a439c9a 100644
--- a/src/crankshaft/s390/lithium-s390.cc
+++ b/src/crankshaft/s390/lithium-s390.cc
@@ -2318,10 +2318,5 @@ LInstruction* LChunkBuilder::DoLoadFieldByIndex(HLoadFieldByIndex* instr) {
   return AssignPointerMap(result);
 }
 
-LInstruction* LChunkBuilder::DoStoreFrameContext(HStoreFrameContext* instr) {
-  LOperand* context = UseRegisterAtStart(instr->context());
-  return new (zone()) LStoreFrameContext(context);
-}
-
 }  // namespace internal
 }  // namespace v8