[runtime] Remove the redundant %_IsObject intrinsic.

src/ppc/lithium-codegen-ppc.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_PPC_LITHIUM_CODEGEN_PPC_H_
 #define V8_PPC_LITHIUM_CODEGEN_PPC_H_
 
 #include "src/ppc/lithium-ppc.h"
 
 #include "src/ppc/lithium-gap-resolver-ppc.h"
@@ skipping 236 matching lines @@
                        CRegister cr = cr7);
   void EmitNumberUntagD(LNumberUntagD* instr, Register input,
                         DoubleRegister result, NumberUntagDMode mode);
 
   // Emits optimized code for typeof x == "y".  Modifies input register.
   // Returns the condition on which a final split to
   // true and false label should be made, to optimize fallthrough.
   Condition EmitTypeofIs(Label* true_label, Label* false_label, Register input,
                          Handle<String> type_name);
 
-  // Emits optimized code for %_IsObject(x).  Preserves input register.
-  // Returns the condition on which a final split to
-  // true and false label should be made, to optimize fallthrough.
-  Condition EmitIsObject(Register input, Register temp1, Label* is_not_object,
-                         Label* is_object);
-
   // Emits optimized code for %_IsString(x).  Preserves input register.
   // Returns the condition on which a final split to
   // true and false label should be made, to optimize fallthrough.
   Condition EmitIsString(Register input, Register temp1, Label* is_not_string,
                          SmiCheck check_needed);
 
   // Emits optimized code for %_IsConstructCall().
   // Caller should branch on equal condition.
   void EmitIsConstructCall(Register temp1, Register temp2);
 
@@ skipping 88 matching lines @@
   LCodeGen* codegen_;
   Label entry_;
   Label exit_;
   Label* external_exit_;
   int instruction_index_;
 };
 }
 }  // namespace v8::internal
 
 #endif  // V8_PPC_LITHIUM_CODEGEN_PPC_H_