Revert r10908 due to flakiness and crashes.

src/arm/lithium-arm.cc

Index: src/arm/lithium-arm.cc
diff --git a/src/arm/lithium-arm.cc b/src/arm/lithium-arm.cc
index 108a6de6276f0eb57bab78a2be860c427a52b40b..b747ab81558dd36a041a3d512396c1bb813be55c 100644
--- a/src/arm/lithium-arm.cc
+++ b/src/arm/lithium-arm.cc
@@ -1170,7 +1170,7 @@ LInstruction* LChunkBuilder::DoInvokeFunction(HInvokeFunction* instr) {
 
 LInstruction* LChunkBuilder::DoUnaryMathOperation(HUnaryMathOperation* instr) {
   BuiltinFunctionId op = instr->op();
-  if (op == kMathLog || op == kMathSin || op == kMathCos || op == kMathTan) {
+  if (op == kMathLog || op == kMathSin || op == kMathCos) {
     LOperand* input = UseFixedDouble(instr->value(), d2);
     LUnaryMathOperation* result = new(zone()) LUnaryMathOperation(input, NULL);
     return MarkAsCall(DefineFixedDouble(result, d2), instr);