Improve interpreter to interpreter invokes.

The interpreter constructs a shadow frame instead of arg array to make
interpreter to interpreter transitions faster. This adds a pointer to
an entry for the interpreter to each method.

Change-Id: If48911d3aa3470847b8548a9e92090b829f4f254
diff --git a/src/interpreter/interpreter.h b/src/interpreter/interpreter.h
index cf47b68..94fdff1 100644
--- a/src/interpreter/interpreter.h
+++ b/src/interpreter/interpreter.h
@@ -47,6 +47,9 @@
                                        ShadowFrame& shadow_frame)
     SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
+extern JValue EnterInterpreterFromInterpreter(Thread* self, ShadowFrame* shadow_frame)
+    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+
 }  // namespace interpreter
 }  // namespace art