Implement System.arraycopy intrinsic for arm.

Change-Id: I58ae1af5103e281fe59fbe022b718d6d8f293a5e
diff --git a/compiler/utils/arm/assembler_arm.h b/compiler/utils/arm/assembler_arm.h
index 967b191..69ecc8f 100644
--- a/compiler/utils/arm/assembler_arm.h
+++ b/compiler/utils/arm/assembler_arm.h
@@ -832,6 +832,8 @@
                                      uint32_t immediate,
                                      ShifterOperand* shifter_op) = 0;
 
+  virtual bool ShifterOperandCanAlwaysHold(uint32_t immediate);
+
   static bool IsInstructionForExceptionHandling(uintptr_t pc);
 
   virtual void CompareAndBranchIfZero(Register r, Label* label) = 0;