Updating comment in Logging.java.

This CL changed the behavior of the logging APIs:
https://webrtc-review.googlesource.com/c/src/+/4160

They now no longer automatically load the native library. So the
comment needs to be updated. This change broke at least one application
that was trying to enable logging before anything else.

NOTRY=True
TBR=sakal@webrtc.org

Bug: None
Change-Id: I845aa8de2eebf3687884fbf69668f56e11a3d93c
Reviewed-on: https://webrtc-review.googlesource.com/6200
Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
Commit-Queue: Taylor Brandstetter <deadbeef@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20127}
diff --git a/rtc_base/java/src/org/webrtc/Logging.java b/rtc_base/java/src/org/webrtc/Logging.java
index 3c3b7a6..1afb687 100644
--- a/rtc_base/java/src/org/webrtc/Logging.java
+++ b/rtc_base/java/src/org/webrtc/Logging.java
@@ -24,7 +24,13 @@
  * - Logging.enableLogTimeStamps
  * - Logging.enableTracing
  * - Logging.enableLogToDebugOutput
- * Using native logging requires the presence of the jingle_peerconnection_so library.
+ *
+ * Using these APIs requires that the native library is loaded. For example:
+ *
+ * System.loadLibrary("jingle_peerconnection_so")
+ *
+ * Many objects (such as PeerConnectionFactory) do this automatically when
+ * constructed.
  */
 public class Logging {
   private static final Logger fallbackLogger = createFallbackLogger();