Fix reporting of width/height

1. maybeRenotifyVideoSizeChanged should report reported* variables
2. Add check into maybeNotifyVideoSizeChanged to suppress reporting
   in the case that the width and height are still unknown.

Issue: #3007

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160879625

library/core/src/main/java/com/google/android/exoplayer2/video/MediaCodecVideoRenderer.java

@@ -700,9 +700,10 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
   }
 
   private void maybeNotifyVideoSizeChanged() {
-    if (reportedWidth != currentWidth || reportedHeight != currentHeight
+    if ((currentWidth != Format.NO_VALUE || currentHeight != Format.NO_VALUE)
+      && (reportedWidth != currentWidth || reportedHeight != currentHeight
         || reportedUnappliedRotationDegrees != currentUnappliedRotationDegrees
-        || reportedPixelWidthHeightRatio != currentPixelWidthHeightRatio) {
+        || reportedPixelWidthHeightRatio != currentPixelWidthHeightRatio)) {
       eventDispatcher.videoSizeChanged(currentWidth, currentHeight, currentUnappliedRotationDegrees,
           currentPixelWidthHeightRatio);
       reportedWidth = currentWidth;
@@ -714,8 +715,8 @@ public class MediaCodecVideoRenderer extends MediaCodecRenderer {
 
   private void maybeRenotifyVideoSizeChanged() {
     if (reportedWidth != Format.NO_VALUE || reportedHeight != Format.NO_VALUE) {
-      eventDispatcher.videoSizeChanged(currentWidth, currentHeight, currentUnappliedRotationDegrees,
-          currentPixelWidthHeightRatio);
+      eventDispatcher.videoSizeChanged(reportedWidth, reportedHeight,
+          reportedUnappliedRotationDegrees, reportedPixelWidthHeightRatio);
     }
   }