Add 'Us' suffix to WebvttCueInfo.{start,end}Time

Clarify that the units used here are microseconds

PiperOrigin-RevId: 286200583

library/core/src/main/java/com/google/android/exoplayer2/text/webvtt/WebvttCueInfo.java

@@ -22,12 +22,12 @@ import com.google.android.exoplayer2.text.Cue;
 public final class WebvttCueInfo {
 
   public final Cue cue;
-  public final long startTime;
-  public final long endTime;
+  public final long startTimeUs;
+  public final long endTimeUs;
 
   public WebvttCueInfo(Cue cue, long startTimeUs, long endTimeUs) {
     this.cue = cue;
-    this.startTime = startTimeUs;
-    this.endTime = endTimeUs;
+    this.startTimeUs = startTimeUs;
+    this.endTimeUs = endTimeUs;
   }
 }

library/core/src/main/java/com/google/android/exoplayer2/text/webvtt/WebvttSubtitle.java

@@ -42,8 +42,8 @@ import java.util.List;
       WebvttCueInfo cueInfo = cueInfos.get(cueIndex);
       this.cues.add(cueInfo.cue);
       int arrayIndex = cueIndex * 2;
-      cueTimesUs[arrayIndex] = cueInfo.startTime;
-      cueTimesUs[arrayIndex + 1] = cueInfo.endTime;
+      cueTimesUs[arrayIndex] = cueInfo.startTimeUs;
+      cueTimesUs[arrayIndex + 1] = cueInfo.endTimeUs;
     }
     sortedCueTimesUs = Arrays.copyOf(cueTimesUs, cueTimesUs.length);
     Arrays.sort(sortedCueTimesUs);