Image transcoding: Add support for bmp image format.

With this change we will now support loading bitmaps from all the formats documented [here](https://developer.android.com/guide/topics/media/media-formats#image-formats) except for gifs (because they are animated). Java doc is added to express this.

PiperOrigin-RevId: 535610152
(cherry picked from commit 7740ccc9382c55e246f5b7e5ea4e120d99b662bc)

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/DefaultAssetLoaderFactory.java

@@ -115,17 +115,10 @@ public final class DefaultAssetLoaderFactory implements AssetLoader.Factory {
       return false;
       return false;
     }
     }
     if (localConfiguration.mimeType != null) {
     if (localConfiguration.mimeType != null) {
-      ImmutableList<String> supportedMimeTypes =
-          ImmutableList.of(
-              MimeTypes.IMAGE_PNG,
-              MimeTypes.IMAGE_WEBP,
-              MimeTypes.IMAGE_JPEG,
-              MimeTypes.IMAGE_HEIC,
-              MimeTypes.IMAGE_HEIF);
-      return supportedMimeTypes.contains(localConfiguration.mimeType);
+      return MimeTypes.isImage(localConfiguration.mimeType);
     }
     }
     ImmutableList<String> supportedImageTypes =
     ImmutableList<String> supportedImageTypes =
-        ImmutableList.of(".png", ".webp", ".jpg", ".jpeg", ".heic", ".heif");
+        ImmutableList.of(".png", ".webp", ".jpg", ".jpeg", ".heic", ".heif", ".bmp");
     String uriPath = checkNotNull(localConfiguration.uri.getPath());
     String uriPath = checkNotNull(localConfiguration.uri.getPath());
     int fileExtensionStart = uriPath.lastIndexOf(".");
     int fileExtensionStart = uriPath.lastIndexOf(".");
     if (fileExtensionStart < 0) {
     if (fileExtensionStart < 0) {

library/transformer/src/main/java/com/google/android/exoplayer2/transformer/ImageAssetLoader.java

@@ -45,7 +45,13 @@ import com.google.common.util.concurrent.MoreExecutors;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.ScheduledExecutorService;
 
 
-/** An {@link AssetLoader} implementation that loads images into {@link Bitmap} instances. */
+/**
+ * An {@link AssetLoader} implementation that loads images into {@link Bitmap} instances.
+ *
+ * <p>Supports the image formats listed <a
+ * href="https://developer.android.com/guide/topics/media/media-formats#image-formats">here</a>
+ * except from GIFs, which could exhibit unexpected behavior.
+ */
 public final class ImageAssetLoader implements AssetLoader {
 public final class ImageAssetLoader implements AssetLoader {
 
 
   /** An {@link AssetLoader.Factory} for {@link ImageAssetLoader} instances. */
   /** An {@link AssetLoader.Factory} for {@link ImageAssetLoader} instances. */