Add weight to compiled/interpreter transitions.

Also:
- Cleanup logging.
- Check ArtMethod status before adding compilation requests.
- Don't request osr compilation if we know AddSamples does not come
  from a back edge.

Bug: 27865109

Change-Id: I84512f7d957b61ce2458360ed430adb151830278
diff --git a/runtime/jit/jit_code_cache.h b/runtime/jit/jit_code_cache.h
index 9f18c70..f31cc51 100644
--- a/runtime/jit/jit_code_cache.h
+++ b/runtime/jit/jit_code_cache.h
@@ -186,6 +186,8 @@
 
   void Dump(std::ostream& os) REQUIRES(!lock_);
 
+  bool IsOsrCompiled(ArtMethod* method) REQUIRES(!lock_);
+
  private:
   // Take ownership of maps.
   JitCodeCache(MemMap* code_map,