[intrinsics] Drop the now obsolete %_DoubleHi and %_DoubleLo intrinsics.

src/crankshaft/arm/lithium-arm.cc

Index: src/crankshaft/arm/lithium-arm.cc
diff --git a/src/crankshaft/arm/lithium-arm.cc b/src/crankshaft/arm/lithium-arm.cc
index 538b3092b3878ae7f8a7739a4df27c9fd96722fc..3bf5e60b10b86e86b2e9b8bf5c02b441ca940e0b 100644
--- a/src/crankshaft/arm/lithium-arm.cc
+++ b/src/crankshaft/arm/lithium-arm.cc
@@ -1980,13 +1980,6 @@ LInstruction* LChunkBuilder::DoClampToUint8(HClampToUint8* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoDoubleBits(HDoubleBits* instr) {
-  HValue* value = instr->value();
-  DCHECK(value->representation().IsDouble());
-  return DefineAsRegister(new(zone()) LDoubleBits(UseRegister(value)));
-}
-
-
 LInstruction* LChunkBuilder::DoReturn(HReturn* instr) {
   LOperand* context = info()->IsStub()
       ? UseFixed(instr->context(), cp)