OPTI-1528: check whether the label is null or blank

Author: adadukin-dolby

ui/src/main/java/com/theoplayer/android/ui/Helper.kt

@@ -93,7 +93,7 @@ fun rememberTrackLabel(
             }
         },
     )
-    if (!label.isNullOrEmpty()) {
+    if (!label.isNullOrBlank()) {
         return@remember label
     }
     val localisedLanguage = track.localisedLanguage

ui/src/main/java/com/theoplayer/android/ui/util/CeaUtil.kt

@@ -1,12 +1,14 @@
 package com.theoplayer.android.ui.util
 
+import androidx.annotation.CheckResult
 import androidx.annotation.IntRange
 
 private val CEA_FORMATTING_REGEX = "^CC(\\d+)$".toRegex()
 
 /**
  * Checks whether a provided label is CEA-608 or CEA-708 formed.
  */
+@CheckResult
 internal fun isLabelCeaFormatted(label: String?): Boolean {
     if (label == null) {
         return false
@@ -32,6 +34,7 @@ internal fun isLabelCeaFormatted(label: String?): Boolean {
  * @return an optional string composed of a [channelNumber] and a prepended
  * "CC" suffix, or `null` if the channel number is invalid.
  */
+@CheckResult
 internal fun getLabelForChannelNumber(
     @IntRange(from = 0L, to = 63L) channelNumber: Int?,
 ): String? {