[builtins] Refactor the remaining Date builtins.

src/crankshaft/mips/lithium-mips.cc

Index: src/crankshaft/mips/lithium-mips.cc
diff --git a/src/crankshaft/mips/lithium-mips.cc b/src/crankshaft/mips/lithium-mips.cc
index 535946af2f4fda3e855935eba70e266ddeac4f69..a9978e1068cf1e1a91895f53cf0ead23eb473344 100644
--- a/src/crankshaft/mips/lithium-mips.cc
+++ b/src/crankshaft/mips/lithium-mips.cc
@@ -1772,14 +1772,6 @@ LInstruction* LChunkBuilder::DoMapEnumLength(HMapEnumLength* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoDateField(HDateField* instr) {
-  LOperand* object = UseFixed(instr->value(), a0);
-  LDateField* result =
-      new(zone()) LDateField(object, FixedTemp(a1), instr->index());
-  return MarkAsCall(DefineFixed(result, v0), instr, CANNOT_DEOPTIMIZE_EAGERLY);
-}
-
-
 LInstruction* LChunkBuilder::DoSeqStringGetChar(HSeqStringGetChar* instr) {
   LOperand* string = UseRegisterAtStart(instr->string());
   LOperand* index = UseRegisterOrConstantAtStart(instr->index());