Refactor reflective method invocation.

Move invocation code out of JNI internal into reflection, including ArgArray
code. Make reflective invocation use the ArgArray to build arguments rather
than allocating a jvalue[] and unboxing arguments into that.
Move reflection part of jni_internal_test into reflection_test.
Make greater use of fast JNI.

Change-Id: Ib381372df5f9a83679e30e7275de24fa0e6b1057
diff --git a/runtime/native/java_lang_reflect_Constructor.cc b/runtime/native/java_lang_reflect_Constructor.cc
index c06bf4c..a22d7ca 100644
--- a/runtime/native/java_lang_reflect_Constructor.cc
+++ b/runtime/native/java_lang_reflect_Constructor.cc
@@ -22,7 +22,7 @@
 #include "mirror/object-inl.h"
 #include "object_utils.h"
 #include "reflection.h"
-#include "scoped_thread_state_change.h"
+#include "scoped_fast_native_object_access.h"
 #include "well_known_classes.h"
 
 namespace art {
@@ -35,8 +35,7 @@
  * with an interface, array, or primitive class.
  */
 static jobject Constructor_newInstance(JNIEnv* env, jobject javaMethod, jobjectArray javaArgs) {
-  // TODO: ScopedFastNativeObjectAccess
-  ScopedObjectAccess soa(env);
+  ScopedFastNativeObjectAccess soa(env);
   jobject art_method = soa.Env()->GetObjectField(
       javaMethod, WellKnownClasses::java_lang_reflect_AbstractMethod_artMethod);