Allow implicit 'close your eyes' of native methods. This will hopefully fix issue 3466.

vm/intermediate_language_x64.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 471 matching lines @@
 
 void NativeCallComp::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(locs()->temp(0).reg() == RAX);
   ASSERT(locs()->temp(1).reg() == RBX);
   ASSERT(locs()->temp(2).reg() == R10);
   Register result = locs()->out().reg();
 
   // Push the result place holder initialized to NULL.
   __ PushObject(Object::ZoneHandle());
   // Pass a pointer to the first argument in RAX.
-  if (!has_optional_parameters()) {
-    __ leaq(RAX, Address(RBP, (1 + argument_count()) * kWordSize));
+  intptr_t arg_count = argument_count();
+  if (is_implicit_native_closure()) {
+    arg_count += 1;
+  }
+  if (!has_optional_parameters() && !is_implicit_native_closure()) {
+    __ leaq(RAX, Address(RBP, (1 + arg_count) * kWordSize));
   } else {
     __ leaq(RAX,
             Address(RBP, ParsedFunction::kFirstLocalSlotIndex * kWordSize));
   }
   __ movq(RBX, Immediate(reinterpret_cast<uword>(native_c_function())));
-  __ movq(R10, Immediate(argument_count()));
+  __ movq(R10, Immediate(arg_count));
   compiler->GenerateCall(token_index(),
                          try_index(),
                          &StubCode::CallNativeCFunctionLabel(),
                          PcDescriptors::kOther);
   __ popq(result);
 }
 
 
 LocationSummary* LoadIndexedComp::MakeLocationSummary() const {
   const intptr_t kNumInputs = 2;
@@ skipping 1136 matching lines @@
                                  instance_call()->argument_names());
   }
   __ Bind(&done);
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64