Remove redundant initializers from WebRTC Java code.

Removes redundant field initializers such as null, 0 and false.

Bug: webrtc:9742
Change-Id: I1e54f6c6000885cf95f7af8e2701875a78445497
Reviewed-on: https://webrtc-review.googlesource.com/99481
Reviewed-by: Henrik Andreassson <henrika@webrtc.org>
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24676}

sdk/android/api/org/webrtc/DataChannel.java

@@ -22,7 +22,7 @@ public class DataChannel {
     // Optional unsigned short in WebIDL, -1 means unspecified.
     public int maxRetransmits = -1;
     public String protocol = "";
-    public boolean negotiated = false;
+    public boolean negotiated;
     // Optional unsigned short in WebIDL, -1 means unspecified.
     public int id = -1;