Clean up handling of global cell stores in the optimizing compiler.

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 1ac152d6a7ec605d725dc8c5adfe4d8dbe853d89..643d0ebe606a422998d3c8fc4dee5986b5b2ebac 100644
--- a/src/arm/lithium-arm.cc
+++ b/src/arm/lithium-arm.cc
@@ -1779,11 +1779,12 @@ LInstruction* LChunkBuilder::DoLoadGlobalGeneric(HLoadGlobalGeneric* instr) {
 
 
 LInstruction* LChunkBuilder::DoStoreGlobalCell(HStoreGlobalCell* instr) {
-  LOperand* temp = TempRegister();
-  LOperand* value = UseTempRegister(instr->value());
-  LInstruction* result = new LStoreGlobalCell(value, temp);
-  if (instr->RequiresHoleCheck()) result = AssignEnvironment(result);
-  return result;
+  LOperand* value = UseRegister(instr->value());
+  // Use a temp to check the value in the cell in the case where we perform
+  // a hole check.
+  return instr->RequiresHoleCheck()
+      ? AssignEnvironment(new LStoreGlobalCell(value, TempRegister()))
+      : new LStoreGlobalCell(value, NULL);
 }