Encode frame info using varints.

This saves 0.3% of oat file size.

Test: test-art-host-gtest-stack_map_test
Change-Id: I85003946a9579f03cb1ed2b5e9b2c62b3efe6734
diff --git a/compiler/optimizing/stack_map_stream.h b/compiler/optimizing/stack_map_stream.h
index de79f49..a5f7ff3 100644
--- a/compiler/optimizing/stack_map_stream.h
+++ b/compiler/optimizing/stack_map_stream.h
@@ -98,7 +98,7 @@
   void CreateDexRegisterMap();
 
   const InstructionSet instruction_set_;
-  uint32_t frame_size_in_bytes_ = 0;
+  uint32_t packed_frame_size_ = 0;
   uint32_t core_spill_mask_ = 0;
   uint32_t fp_spill_mask_ = 0;
   uint32_t num_dex_registers_ = 0;