Remove the FrameSizeLocals field which appears to be unused (write-only).

src/IceTargetLoweringX8632.h

Index: src/IceTargetLoweringX8632.h
diff --git a/src/IceTargetLoweringX8632.h b/src/IceTargetLoweringX8632.h
index 79557ae52b8b6f1c8c5f2b2c1db5516af20e9b88..4213a595d930c449d101162c4744f369511ac417 100644
--- a/src/IceTargetLoweringX8632.h
+++ b/src/IceTargetLoweringX8632.h
@@ -567,7 +567,6 @@ protected:
   const X86InstructionSet InstructionSet;
   bool IsEbpBasedFrame;
   bool NeedsStackAlignment;
-  size_t FrameSizeLocals;
   size_t SpillAreaSizeBytes;
   llvm::SmallBitVector TypeToRegisterSet[IceType_NUM];
   llvm::SmallBitVector ScratchRegs;