[intrinsics] Kill the %_IsMinusZero intrinsic.

src/crankshaft/x87/lithium-x87.cc

Index: src/crankshaft/x87/lithium-x87.cc
diff --git a/src/crankshaft/x87/lithium-x87.cc b/src/crankshaft/x87/lithium-x87.cc
index 09f97d35b213edfcff84c09215d14e3eaf34a5c1..66342a0bc930c2c2e3009c2d391ce82309a9b117 100644
--- a/src/crankshaft/x87/lithium-x87.cc
+++ b/src/crankshaft/x87/lithium-x87.cc
@@ -1715,13 +1715,6 @@ LInstruction* LChunkBuilder::DoCompareHoleAndBranch(
 }
 
 
-LInstruction* LChunkBuilder::DoCompareMinusZeroAndBranch(
-    HCompareMinusZeroAndBranch* instr) {
-  LOperand* value = UseRegisterAtStart(instr->value());
-  return new (zone()) LCompareMinusZeroAndBranch(value);
-}
-
-
 LInstruction* LChunkBuilder::DoIsStringAndBranch(HIsStringAndBranch* instr) {
   DCHECK(instr->value()->representation().IsTagged());
   LOperand* temp = TempRegister();