Collect and output a few dex2oat statistics.

Not sure how useful this is. Suggestions welcome.

Change-Id: I339de66a9964d18b11a482f549e891a57831e10e
diff --git a/src/compiler.h b/src/compiler.h
index 89173eb..ddc05d5 100644
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -147,6 +147,14 @@
 
   bool image_;
 
+  size_t dex_file_count_;
+  size_t class_count_;
+  size_t abstract_method_count_;
+  size_t native_method_count_;
+  size_t regular_method_count_;
+  size_t instruction_count_;
+  uint64_t start_ns_;
+
   const std::set<std::string>* image_classes_;
 
   DISALLOW_COPY_AND_ASSIGN(Compiler);