Mark lazily-patched native calls correctly as patchable.

runtime/vm/intermediate_language_x64.cc

Index: runtime/vm/intermediate_language_x64.cc
diff --git a/runtime/vm/intermediate_language_x64.cc b/runtime/vm/intermediate_language_x64.cc
index 9510d28058ea186ae383b130046c5cfc3f1b532b..097df6ec33f1ff5c69f4efecbd4fc5d080f2c317 100644
--- a/runtime/vm/intermediate_language_x64.cc
+++ b/runtime/vm/intermediate_language_x64.cc
@@ -815,15 +815,17 @@ void NativeCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
     stub_entry = StubCode::CallBootstrapCFunction_entry();
     ExternalLabel label(NativeEntry::LinkNativeCallEntry());
     __ LoadNativeEntry(RBX, &label, kPatchable);
+    compiler->GeneratePatchableCall(token_pos(), *stub_entry,
+                                    RawPcDescriptors::kOther, locs());
   } else {
     stub_entry = (is_bootstrap_native())
                      ? StubCode::CallBootstrapCFunction_entry()
                      : StubCode::CallNativeCFunction_entry();
     const ExternalLabel label(reinterpret_cast<uword>(native_c_function()));
     __ LoadNativeEntry(RBX, &label, kNotPatchable);
+    compiler->GenerateCall(token_pos(), *stub_entry, RawPcDescriptors::kOther,
+                           locs());
   }
-  compiler->GenerateCall(token_pos(), *stub_entry, RawPcDescriptors::kOther,
-                         locs());
   __ popq(result);
 }