Revert "Revert "[optimizing] Enable x86 long support.""

This reverts commit 154552e666347d41d95d7619c6ee56249ff4feca.

Change-Id: Idc726551c249a888b7ff5fde8508ae50e81b2e13
diff --git a/compiler/optimizing/code_generator_x86.h b/compiler/optimizing/code_generator_x86.h
index f5a9b7d..c5763de 100644
--- a/compiler/optimizing/code_generator_x86.h
+++ b/compiler/optimizing/code_generator_x86.h
@@ -245,6 +245,8 @@
     return type == Primitive::kPrimLong;
   }
 
+  bool ShouldSplitLongMoves() const OVERRIDE { return true; }
+
   Label* GetFrameEntryLabel() { return &frame_entry_label_; }
 
  private: