Make toUpperCase conversions locale invariant

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=190942033

library/core/src/main/java/com/google/android/exoplayer2/util/MimeTypes.java

@@ -200,7 +200,7 @@ public final class MimeTypes {
         String objectTypeString = codec.substring(5); // remove the 'mp4a.' prefix
         if (objectTypeString.length() >= 2) {
           try {
-            String objectTypeHexString = objectTypeString.toUpperCase().substring(0, 2);
+            String objectTypeHexString = Util.toUpperInvariant(objectTypeString.substring(0, 2));
             int objectTypeInt = Integer.parseInt(objectTypeHexString, 16);
             mimeType = getMimeTypeFromMp4ObjectType(objectTypeInt);
           } catch (NumberFormatException ignored) {

library/core/src/main/java/com/google/android/exoplayer2/util/Util.java

@@ -306,6 +306,16 @@ public final class Util {
     return text == null ? null : text.toLowerCase(Locale.US);
   }
 
+  /**
+   * Converts text to upper case using {@link Locale#US}.
+   *
+   * @param text The text to convert.
+   * @return The upper case text, or null if {@code text} is null.
+   */
+  public static String toUpperInvariant(String text) {
+    return text == null ? null : text.toUpperCase(Locale.US);
+  }
+
   /**
    * Divides a {@code numerator} by a {@code denominator}, returning the ceiled result.
    *

library/hls/src/test/java/com/google/android/exoplayer2/source/hls/playlist/HlsMediaPlaylistParserTest.java

@@ -20,12 +20,12 @@ import static com.google.common.truth.Truth.assertThat;
 import android.net.Uri;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.source.hls.playlist.HlsMediaPlaylist.Segment;
+import com.google.android.exoplayer2.util.Util;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.Charset;
 import java.util.List;
-import java.util.Locale;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.robolectric.RobolectricTestRunner;
@@ -122,7 +122,7 @@ public class HlsMediaPlaylistParserTest {
         .isEqualTo("https://priv.example.com/key.php?r=2682");
     // 0xA7A == 2682.
     assertThat(segment.encryptionIV).isNotNull();
-    assertThat(segment.encryptionIV.toUpperCase(Locale.getDefault())).isEqualTo("A7A");
+    assertThat(Util.toUpperInvariant(segment.encryptionIV)).isEqualTo("A7A");
     assertThat(segment.byterangeLength).isEqualTo(51740);
     assertThat(segment.byterangeOffset).isEqualTo(2147586650L);
     assertThat(segment.url).isEqualTo("https://priv.example.com/fileSequence2682.ts");
@@ -134,7 +134,7 @@ public class HlsMediaPlaylistParserTest {
         .isEqualTo("https://priv.example.com/key.php?r=2682");
     // 0xA7B == 2683.
     assertThat(segment.encryptionIV).isNotNull();
-    assertThat(segment.encryptionIV.toUpperCase(Locale.getDefault())).isEqualTo("A7B");
+    assertThat(Util.toUpperInvariant(segment.encryptionIV)).isEqualTo("A7B");
     assertThat(segment.byterangeLength).isEqualTo(C.LENGTH_UNSET);
     assertThat(segment.byterangeOffset).isEqualTo(0);
     assertThat(segment.url).isEqualTo("https://priv.example.com/fileSequence2683.ts");