Migrate AudioFocusChangeListener to browser and always send GAIN

content/public/test/android/javatests/src/org/chromium/content/browser/test/util/DOMUtils.java

Index: content/public/test/android/javatests/src/org/chromium/content/browser/test/util/DOMUtils.java
diff --git a/content/public/test/android/javatests/src/org/chromium/content/browser/test/util/DOMUtils.java b/content/public/test/android/javatests/src/org/chromium/content/browser/test/util/DOMUtils.java
index 235e4a3f391c88a56fafd732effbc803cce4794c..a1d5836605dcf9323497d340517af39054732a4b 100644
--- a/content/public/test/android/javatests/src/org/chromium/content/browser/test/util/DOMUtils.java
+++ b/content/public/test/android/javatests/src/org/chromium/content/browser/test/util/DOMUtils.java
@@ -22,6 +22,16 @@ import java.util.concurrent.TimeoutException;
  */
 public class DOMUtils {
     /**
+     * Video element is playing.
+     */
+    public static final int VIDEO_STATE_PLAYING = 0;
+
+    /**
+     * Video element is paused.
+     */
+    public static final int VIDEO_STATE_PAUSED = 1;
+
+    /**
      * Pauses the video with given {@code nodeId}.
      */
     public static void pauseVideo(final WebContents webContents, final String nodeId)
@@ -44,17 +54,26 @@ public class DOMUtils {
     }
 
     /**
-     * Waits until the playback of the video with given {@code nodeId} has started.
+     * Waits until the playback of the video with given {@code nodeId} is {@code videoState}.
      *
-     * @return Whether the playback has started.
+     * @return Whether the playback state is now {@code videoState}.
      */
-    public static boolean waitForVideoPlay(final WebContents webContents, final String nodeId)
+    public static boolean waitForVideoState(final WebContents webContents,
+            final String nodeId, final int videoState)
             throws InterruptedException {
         return CriteriaHelper.pollForCriteria(new Criteria() {
             @Override
             public boolean isSatisfied() {
                 try {
-                    return !DOMUtils.isVideoPaused(webContents, nodeId);
+                    switch (videoState) {
+                        case VIDEO_STATE_PLAYING:
+                            return !DOMUtils.isVideoPaused(webContents, nodeId);
+                        case VIDEO_STATE_PAUSED:
+                            return DOMUtils.isVideoPaused(webContents, nodeId);
+                        default:
+                            throw new IllegalArgumentException(
+                                    "Cannot wait for videoState: " + videoState);
+                    }
                 } catch (InterruptedException e) {
                     // Intentionally do nothing
                     return false;