Revert "Implement transceiver.stop()"

This reverts commit 11dc6571cb4ff3e71dee1557dfff8d9076e108d3.

Reason for revert: Breaks Chromium WPT tests

Original change's description:
> Implement transceiver.stop()
> 
> This adds RtpTransceiver.StopStandard(), which behaves according to
> the specification at
> https://w3c.github.io/webrtc-pc/#dom-rtcrtptransceiver-stop
> 
> It modifies RTCPeerConnection.getTransceivers() to return only
> transceivers that have not been stopped.
> 
> Rebase of armax' https://webrtc-review.googlesource.com/c/src/+/172762
> 
> Bug: chromium:980879
> Change-Id: I7d383ee874ccc0a006fdcf280496b5d4235425ce
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/180580
> Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
> Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
> Reviewed-by: Guido Urdaneta <guidou@webrtc.org>
> Commit-Queue: Harald Alvestrand <hta@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#31893}

TBR=sakal@webrtc.org,kthelgason@webrtc.org,hta@webrtc.org,guidou@webrtc.org,marinaciocea@webrtc.org

Change-Id: Ibdc24f7d41e481293ca74ba6d1572de64f7e4654
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:980879
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/181262
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31897}
diff --git a/sdk/android/api/org/webrtc/RtpTransceiver.java b/sdk/android/api/org/webrtc/RtpTransceiver.java
index 021cc90..64d8eb4 100644
--- a/sdk/android/api/org/webrtc/RtpTransceiver.java
+++ b/sdk/android/api/org/webrtc/RtpTransceiver.java
@@ -206,34 +206,13 @@
   }
 
   /**
-   * The Stop method will for the time being call the StopInternal method.
-   * After a migration procedure, stop() will be equivalent to StopStandard.
+   * The Stop method irreversibly stops the RtpTransceiver. The sender of this
+   * transceiver will no longer send, the receiver will no longer receive.
+   * https://w3c.github.io/webrtc-pc/#dom-rtcrtptransceiver-stop
    */
   public void stop() {
     checkRtpTransceiverExists();
-    nativeStopInternal(nativeRtpTransceiver);
-  }
-
-  /**
-   * The StopInternal method stops the RtpTransceiver, like Stop, but goes
-   * immediately to Stopped state.
-   */
-  public void stopInternal() {
-    checkRtpTransceiverExists();
-    nativeStopInternal(nativeRtpTransceiver);
-  }
-
-  /**
-   * The StopStandard method irreversibly stops the RtpTransceiver. The sender
-   * of this transceiver will no longer send, the receiver will no longer
-   * receive.
-   *
-   * <p>The transceiver will enter Stopping state and signal NegotiationNeeded.
-   * https://w3c.github.io/webrtc-pc/#dom-rtcrtptransceiver-stop
-   */
-  public void stopStandard() {
-    checkRtpTransceiverExists();
-    nativeStopStandard(nativeRtpTransceiver);
+    nativeStop(nativeRtpTransceiver);
   }
 
   @CalledByNative
@@ -258,8 +237,7 @@
   private static native boolean nativeStopped(long rtpTransceiver);
   private static native RtpTransceiverDirection nativeDirection(long rtpTransceiver);
   private static native RtpTransceiverDirection nativeCurrentDirection(long rtpTransceiver);
-  private static native void nativeStopInternal(long rtpTransceiver);
-  private static native void nativeStopStandard(long rtpTransceiver);
+  private static native void nativeStop(long rtpTransceiver);
   private static native void nativeSetDirection(
       long rtpTransceiver, RtpTransceiverDirection rtpTransceiverDirection);
 }