MIPS: Fix code for InstanceofStub.

Port r24654 (66aa0fb)

BUG=
R=dusan.milosavljevic@imgtec.com

Review URL: https://codereview.chromium.org/661803002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24667 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/mips/code-stubs-mips.cc

@@ -1572,9 +1572,7 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
   __ Branch(&slow, ne, scratch, Operand(JS_FUNCTION_TYPE));
 
   // Null is not instance of anything.
-  __ Branch(&object_not_null,
-            ne,
-            scratch,
+  __ Branch(&object_not_null, ne, object,
             Operand(isolate()->factory()->null_value()));
   if (ReturnTrueFalseObject()) {
     __ LoadRoot(v0, Heap::kFalseValueRootIndex);

src/mips64/code-stubs-mips64.cc

@@ -1542,9 +1542,7 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
   __ Branch(&slow, ne, scratch, Operand(JS_FUNCTION_TYPE));
 
   // Null is not instance of anything.
-  __ Branch(&object_not_null,
-            ne,
-            scratch,
+  __ Branch(&object_not_null, ne, object,
             Operand(isolate()->factory()->null_value()));
   __ li(v0, Operand(Smi::FromInt(1)));
   __ DropAndRet(HasArgsInRegisters() ? 0 : 2);