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

src/mips/builtins-mips.cc

Index: src/mips/builtins-mips.cc
diff --git a/src/mips/builtins-mips.cc b/src/mips/builtins-mips.cc
index 93a10ce098394cfb4c62ff8978746926ec3d106b..b74ec757ae3b087e8e98ad47e0acd9d99e239ca1 100644
--- a/src/mips/builtins-mips.cc
+++ b/src/mips/builtins-mips.cc
@@ -1313,8 +1313,10 @@ void Builtins::Generate_FunctionCall(MacroAssembler* masm) {
     {
       FrameScope scope(masm, StackFrame::INTERNAL);
       __ sll(a0, a0, kSmiTagSize);  // Smi tagged.
-      __ Push(a0, a2);
-      __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
+      __ push(a0);
+      __ mov(a0, a2);
+      ToObjectStub stub(masm->isolate());
+      __ CallStub(&stub);
       __ mov(a2, v0);
 
       __ pop(a0);
@@ -1548,8 +1550,8 @@ static void Generate_ApplyHelper(MacroAssembler* masm, bool targetIsArgument) {
     // Convert the receiver to a regular object.
     // a0: receiver
     __ bind(&call_to_object);
-    __ push(a0);
-    __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
+    ToObjectStub stub(masm->isolate());
+    __ CallStub(&stub);
     __ mov(a0, v0);  // Put object in a0 to match other paths to push_receiver.
     __ Branch(&push_receiver);