[builtins] Introduce proper Float64Tan operator.

src/crankshaft/ia32/lithium-ia32.cc

Index: src/crankshaft/ia32/lithium-ia32.cc
diff --git a/src/crankshaft/ia32/lithium-ia32.cc b/src/crankshaft/ia32/lithium-ia32.cc
index 51295a473fa9087f2a2946fb21a64278407e330d..60024c26a94767db95df308ebeba483ea1ec882d 100644
--- a/src/crankshaft/ia32/lithium-ia32.cc
+++ b/src/crankshaft/ia32/lithium-ia32.cc
@@ -1994,13 +1994,6 @@ LInstruction* LChunkBuilder::DoDoubleBits(HDoubleBits* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoConstructDouble(HConstructDouble* instr) {
-  LOperand* lo = UseRegister(instr->lo());
-  LOperand* hi = UseRegister(instr->hi());
-  return DefineAsRegister(new(zone()) LConstructDouble(hi, lo));
-}
-
-
 LInstruction* LChunkBuilder::DoReturn(HReturn* instr) {
   LOperand* context = info()->IsStub() ? UseFixed(instr->context(), esi) : NULL;
   LOperand* parameter_count = UseRegisterOrConstant(instr->parameter_count());