Update release notes + bump version number

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160663100

RELEASENOTES.md

 # Release notes #
 
+### r2.4.3 ###
+
+* Audio: Workaround custom audio decoders misreporting their maximum supported
+  channel counts ([#2940](https://github.com/google/ExoPlayer/issues/2940)).
+* Audio: Workaround for broken MediaTek raw decoder on some devices
+  ([#2873](https://github.com/google/ExoPlayer/issues/2873)).
+* Captions: Fix TTML captions appearing at the top of the screen
+  ([#2953](https://github.com/google/ExoPlayer/issues/2953)).
+* Captions: Fix handling of some DVB subtitles
+  ([#2957](https://github.com/google/ExoPlayer/issues/2957)).
+* Track selection: Fix setSelectionOverride(index, tracks, null)
+  ([#2988](https://github.com/google/ExoPlayer/issues/2988)).
+* GVR extension: Add support for mono input
+  ([#2710](https://github.com/google/ExoPlayer/issues/2710)).
+* FLAC extension: Fix failing build
+  ([#2977](https://github.com/google/ExoPlayer/pull/2977)).
+* Misc bugfixes.
+
 ### r2.4.2 ###
 
 * Stability: Work around Nexus 10 reboot when playing certain content
-  ([2806](https://github.com/google/ExoPlayer/issues/2806)).
+  ([#2806](https://github.com/google/ExoPlayer/issues/2806)).
 * MP3: Correctly treat MP3s with INFO headers as constant bitrate
-  ([2895](https://github.com/google/ExoPlayer/issues/2895)).
+  ([#2895](https://github.com/google/ExoPlayer/issues/2895)).
 * HLS: Use average rather than peak bandwidth when available
   ([#2863](https://github.com/google/ExoPlayer/issues/2863)).
 * SmoothStreaming: Fix timeline for live streams

constants.gradle

@@ -24,7 +24,7 @@ project.ext {
     supportLibraryVersion = '25.3.1'
     dexmakerVersion = '1.2'
     mockitoVersion = '1.9.5'
-    releaseVersion = 'r2.4.2'
+    releaseVersion = 'r2.4.3'
     modulePrefix = ':';
     if (gradle.ext.has('exoplayerModulePrefix')) {
         modulePrefix += gradle.ext.exoplayerModulePrefix

demo/src/main/AndroidManifest.xml

@@ -16,8 +16,8 @@
 
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.google.android.exoplayer2.demo"
-    android:versionCode="2402"
-    android:versionName="2.4.2">
+    android:versionCode="2403"
+    android:versionName="2.4.3">
 
   <uses-permission android:name="android.permission.INTERNET"/>
   <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerLibraryInfo.java

@@ -24,13 +24,13 @@ public interface ExoPlayerLibraryInfo {
    * The version of the library expressed as a string, for example "1.2.3".
    */
   // Intentionally hardcoded. Do not derive from other constants (e.g. VERSION_INT) or vice versa.
-  String VERSION = "2.4.2";
+  String VERSION = "2.4.3";
 
   /**
    * The version of the library expressed as {@code "ExoPlayerLib/" + VERSION}.
    */
   // Intentionally hardcoded. Do not derive from other constants (e.g. VERSION) or vice versa.
-  String VERSION_SLASHY = "ExoPlayerLib/2.4.2";
+  String VERSION_SLASHY = "ExoPlayerLib/2.4.3";
 
   /**
    * The version of the library expressed as an integer, for example 1002003.
@@ -40,7 +40,7 @@ public interface ExoPlayerLibraryInfo {
    * integer version 123045006 (123-045-006).
    */
   // Intentionally hardcoded. Do not derive from other constants (e.g. VERSION) or vice versa.
-  int VERSION_INT = 2004002;
+  int VERSION_INT = 2004003;
 
   /**
    * Whether the library was compiled with {@link com.google.android.exoplayer2.util.Assertions}