Small optimization for recursive calls: avoid dex cache.

Change-Id: I044757a2f06e535cdc1480c4fc8182b89635baf6
diff --git a/compiler/optimizing/code_generator_arm64.h b/compiler/optimizing/code_generator_arm64.h
index 100dafe..9a99dcc 100644
--- a/compiler/optimizing/code_generator_arm64.h
+++ b/compiler/optimizing/code_generator_arm64.h
@@ -297,6 +297,7 @@
  private:
   // Labels for each block that will be compiled.
   vixl::Label* block_labels_;
+  vixl::Label frame_entry_label_;
 
   LocationsBuilderARM64 location_builder_;
   InstructionCodeGeneratorARM64 instruction_visitor_;