ART: Remove redundant MoveInstructionBefore method

Change-Id: If53d7011197cc6b9c1702a3d98ef11b59eb76f0c
diff --git a/compiler/optimizing/nodes_arm.h b/compiler/optimizing/nodes_arm.h
index 371e8ef..d9f9740e 100644
--- a/compiler/optimizing/nodes_arm.h
+++ b/compiler/optimizing/nodes_arm.h
@@ -26,6 +26,8 @@
         dex_file_(&dex_file),
         element_offset_(static_cast<size_t>(-1)) { }
 
+  bool CanBeMoved() const OVERRIDE { return true; }
+
   void UpdateElementOffset(size_t element_offset) {
     // Use the lowest offset from the requested elements so that all offsets from
     // this base are non-negative because our assemblers emit negative-offset loads