Add DEFINE_JNI() to WebRTC open source

We have added some new features to JNI Zero that requires all C++
implementation files to have a macro call DEFINE_JNI(JavaClassName)
at the end of the file, where JavaClassName is the name of the Java
class whose generated JNI Zero header file is included in the C++ file.
This CL adds this macro call to the end of all C++ files.

Bug: chromium:481689330
Change-Id: I50abcdc0f1fe8cba20377b07577e8821d8cf9221
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/489720
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Commit-Queue: Martin Kong <martinkong@google.com>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#48212}