Use Unique<Cell> and Unique<PropertyCell> in LoadGlobalCell and StoreGlobalCell.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index f62e3fff5135914ced225de11f7962e9c2e53c63..2680c348d6255177386fdc7cd11611a4a3fff1d8 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -2954,7 +2954,7 @@ void LCodeGen::DoReturn(LReturn* instr) {
 
 void LCodeGen::DoLoadGlobalCell(LLoadGlobalCell* instr) {
   Register result = ToRegister(instr->result());
-  __ mov(ip, Operand(Handle<Object>(instr->hydrogen()->cell())));
+  __ mov(ip, Operand(Handle<Object>(instr->hydrogen()->cell().handle())));
   __ ldr(result, FieldMemOperand(ip, Cell::kValueOffset));
   if (instr->hydrogen()->RequiresHoleCheck()) {
     __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
@@ -2981,7 +2981,7 @@ void LCodeGen::DoStoreGlobalCell(LStoreGlobalCell* instr) {
   Register cell = scratch0();
 
   // Load the cell.
-  __ mov(cell, Operand(instr->hydrogen()->cell()));
+  __ mov(cell, Operand(instr->hydrogen()->cell().handle()));
 
   // If the cell we are storing to contains the hole it could have
   // been deleted from the property dictionary. In that case, we need