[runtime] Remove the redundant %_IsObject intrinsic.

src/ppc/lithium-ppc.cc

Index: src/ppc/lithium-ppc.cc
diff --git a/src/ppc/lithium-ppc.cc b/src/ppc/lithium-ppc.cc
index 6841db5d32b31b2e5d2ed4c082d597da208adcfc..bfdbbdff34b1e13bc6e7e11304e73b61b59272b9 100644
--- a/src/ppc/lithium-ppc.cc
+++ b/src/ppc/lithium-ppc.cc
@@ -183,13 +183,6 @@ void LCompareNumericAndBranch::PrintDataTo(StringStream* stream) {
 }
 
 
-void LIsObjectAndBranch::PrintDataTo(StringStream* stream) {
-  stream->Add("if is_object(");
-  value()->PrintTo(stream);
-  stream->Add(") then B%d else B%d", true_block_id(), false_block_id());
-}
-
-
 void LIsStringAndBranch::PrintDataTo(StringStream* stream) {
   stream->Add("if is_string(");
   value()->PrintTo(stream);
@@ -1745,14 +1738,6 @@ LInstruction* LChunkBuilder::DoCompareMinusZeroAndBranch(
 }
 
 
-LInstruction* LChunkBuilder::DoIsObjectAndBranch(HIsObjectAndBranch* instr) {
-  DCHECK(instr->value()->representation().IsTagged());
-  LOperand* value = UseRegisterAtStart(instr->value());
-  LOperand* temp = TempRegister();
-  return new (zone()) LIsObjectAndBranch(value, temp);
-}
-
-
 LInstruction* LChunkBuilder::DoIsStringAndBranch(HIsStringAndBranch* instr) {
   DCHECK(instr->value()->representation().IsTagged());
   LOperand* value = UseRegisterAtStart(instr->value());