Remove unused context-level from LoadLocal/StoreLocal IL instructions.

runtime/vm/flow_graph_builder.cc

Index: runtime/vm/flow_graph_builder.cc
===================================================================
--- runtime/vm/flow_graph_builder.cc	(revision 19781)
+++ runtime/vm/flow_graph_builder.cc	(working copy)
@@ -407,7 +407,7 @@
 Definition* EffectGraphVisitor::BuildStoreTemp(const LocalVariable& local,
                                                Value* value) {
   ASSERT(!local.is_captured());
-  return new StoreLocalInstr(local, value, owner()->context_level());
+  return new StoreLocalInstr(local, value);
 }
 
 
@@ -451,7 +451,7 @@
       return store;
     }
   } else {
-    return new StoreLocalInstr(local, value, owner()->context_level());
+    return new StoreLocalInstr(local, value);
   }
 }
 
@@ -471,7 +471,7 @@
                               Context::variable_offset(local.index()),
                               local.type());
   } else {
-    return new LoadLocalInstr(local, owner()->context_level());
+    return new LoadLocalInstr(local);
   }
 }
 
@@ -1680,7 +1680,7 @@
   const intptr_t deopt_id = Isolate::kNoDeoptId;
   for (int i = 0; i < node->length(); ++i) {
     Value* array = Bind(
-        new LoadLocalInstr(node->temp_local(), owner()->context_level()));
+        new LoadLocalInstr(node->temp_local()));
     Value* index = Bind(new ConstantInstr(Smi::ZoneHandle(Smi::New(i))));
     ValueGraphVisitor for_value(owner(), temp_index());
     node->ElementAt(i)->Visit(&for_value);
@@ -1697,8 +1697,7 @@
     Do(store);
   }
 
-  ReturnDefinition(
-      new LoadLocalInstr(node->temp_local(), owner()->context_level()));
+  ReturnDefinition(new LoadLocalInstr(node->temp_local()));
 }