[intrinsics] Kill the %_IsMinusZero intrinsic.

src/crankshaft/mips64/lithium-mips64.cc

Index: src/crankshaft/mips64/lithium-mips64.cc
diff --git a/src/crankshaft/mips64/lithium-mips64.cc b/src/crankshaft/mips64/lithium-mips64.cc
index 6cfa1b56a43f51a6db2a813ea1ce10a3bbe0ac2d..78dcd4761c66a0fcdd66c7a23b231ad9d69166ac 100644
--- a/src/crankshaft/mips64/lithium-mips64.cc
+++ b/src/crankshaft/mips64/lithium-mips64.cc
@@ -1696,14 +1696,6 @@ LInstruction* LChunkBuilder::DoCompareHoleAndBranch(
 }
 
 
-LInstruction* LChunkBuilder::DoCompareMinusZeroAndBranch(
-    HCompareMinusZeroAndBranch* instr) {
-  LOperand* value = UseRegister(instr->value());
-  LOperand* scratch = TempRegister();
-  return new(zone()) LCompareMinusZeroAndBranch(value, scratch);
-}
-
-
 LInstruction* LChunkBuilder::DoIsStringAndBranch(HIsStringAndBranch* instr) {
   DCHECK(instr->value()->representation().IsTagged());
   LOperand* temp = TempRegister();