Move more IMA extension utils into ImaUtil

These symbols will be referenced from AdTagLoader too in a later change.

PiperOrigin-RevId: 339889990

extensions/ima/src/main/java/com/google/android/exoplayer2/ext/ima/ImaAdsLoader.java

@@ -15,6 +15,9 @@
  */
 package com.google.android.exoplayer2.ext.ima;
 
+import static com.google.android.exoplayer2.ext.ima.ImaUtil.BITRATE_UNSET;
+import static com.google.android.exoplayer2.ext.ima.ImaUtil.TIMEOUT_UNSET;
+import static com.google.android.exoplayer2.ext.ima.ImaUtil.getImaLooper;
 import static com.google.android.exoplayer2.util.Assertions.checkArgument;
 import static com.google.android.exoplayer2.util.Assertions.checkNotNull;
 import static com.google.android.exoplayer2.util.Assertions.checkState;
@@ -461,9 +464,6 @@ public final class ImaAdsLoader
   /** The threshold below which ad cue points are treated as matching, in microseconds. */
   private static final long THRESHOLD_AD_MATCH_US = 1000;
 
-  private static final int TIMEOUT_UNSET = -1;
-  private static final int BITRATE_UNSET = -1;
-
   /** The state of ad playback. */
   @Documented
   @Retention(RetentionPolicy.SOURCE)
@@ -1661,12 +1661,6 @@ public final class ImaAdsLoader
             : timeline.getPeriod(/* periodIndex= */ 0, period).getPositionInWindowMs());
   }
 
-  private static Looper getImaLooper() {
-    // IMA SDK callbacks occur on the main thread. This method can be used to check that the player
-    // is using the same looper, to ensure all interaction with this class is on the main thread.
-    return Looper.getMainLooper();
-  }
-
   private static boolean hasMidrollAdGroups(long[] adGroupTimesUs) {
     int count = adGroupTimesUs.length;
     if (count == 1) {

extensions/ima/src/main/java/com/google/android/exoplayer2/ext/ima/ImaUtil.java

@@ -16,6 +16,7 @@
 package com.google.android.exoplayer2.ext.ima;
 
 import android.content.Context;
+import android.os.Looper;
 import android.view.View;
 import android.view.ViewGroup;
 import androidx.annotation.Nullable;
@@ -130,6 +131,9 @@ import java.util.Set;
     }
   }
 
+  public static final int TIMEOUT_UNSET = -1;
+  public static final int BITRATE_UNSET = -1;
+
   /**
    * Returns the IMA {@link FriendlyObstructionPurpose} corresponding to the given {@link
    * OverlayInfo#purpose}.
@@ -203,6 +207,13 @@ import java.util.Set;
         || adError.getErrorCode() == AdError.AdErrorCode.UNKNOWN_ERROR;
   }
 
+  /** Returns the looper on which all IMA SDK interaction must occur. */
+  public static Looper getImaLooper() {
+    // IMA SDK callbacks occur on the main thread. This method can be used to check that the player
+    // is using the same looper, to ensure all interaction with this class is on the main thread.
+    return Looper.getMainLooper();
+  }
+
   /** Returns a human-readable representation of a video progress update. */
   public static String getStringForVideoProgressUpdate(VideoProgressUpdate videoProgressUpdate) {
     if (VideoProgressUpdate.VIDEO_TIME_NOT_READY.equals(videoProgressUpdate)) {