[stubs] Unify (and optimize) implementation of ToObject.

src/mips64/interface-descriptors-mips64.cc

Index: src/mips64/interface-descriptors-mips64.cc
diff --git a/src/mips64/interface-descriptors-mips64.cc b/src/mips64/interface-descriptors-mips64.cc
index 87c8ffbc84c56b33c18db4a33afc0607a4b8cc0b..953e2545a19becf21ebbdc45ecf7452a8e27135d 100644
--- a/src/mips64/interface-descriptors-mips64.cc
+++ b/src/mips64/interface-descriptors-mips64.cc
@@ -95,6 +95,13 @@ void ToNumberDescriptor::InitializePlatformSpecific(
 }
 
 
+void ToObjectDescriptor::InitializePlatformSpecific(
+    CallInterfaceDescriptorData* data) {
+  Register registers[] = {a0};
+  data->InitializePlatformSpecific(arraysize(registers), registers, nullptr);
+}
+
+
 void NumberToStringDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {a0};