Add Gav1VideoDecoder to watch_time_recorder.cc.

Also print the hash padded with leading 0's to 8 hex digits.

Bug: 1026522
Change-Id: I2f8f8db71619839beccd8723461f0842ea960240
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2042195Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#739218}

media/mojo/services/watch_time_recorder.cc

@@ -50,6 +50,7 @@ enum class VideoDecoderName : int {
   kDav1d = 7,        // Dav1dVideoDecoder
   kFuchsia = 8,      // FuchsiaVideoDecoder
   kMediaPlayer = 9,  // MediaPlayer
+  kLibgav1 = 10,     // Gav1VideoDecoder
 };
 
 static AudioDecoderName ConvertAudioDecoderNameToEnum(const std::string& name) {
@@ -94,6 +95,8 @@ static VideoDecoderName ConvertVideoDecoderNameToEnum(const std::string& name) {
       return VideoDecoderName::kFuchsia;
     case 0x667dc202:
       return VideoDecoderName::kMediaPlayer;
+    case 0x0cd14d5b:
+      return VideoDecoderName::kLibgav1;
     default:
       DLOG_IF(WARNING, !name.empty())
           << "Unknown decoder name encountered; metrics need updating: "

media/mojo/services/watch_time_recorder_unittest.cc

@@ -1556,10 +1556,11 @@ TEST_F(WatchTimeRecorderTest, DISABLED_PrintExpectedDecoderNameHashes) {
       "FFmpegAudioDecoder", "FFmpegVideoDecoder",     "GpuVideoDecoder",
       "MojoVideoDecoder",   "MojoAudioDecoder",       "VpxVideoDecoder",
       "AomVideoDecoder",    "DecryptingAudioDecoder", "DecryptingVideoDecoder",
-      "Dav1dVideoDecoder",  "FuchsiaVideoDecoder",    "MediaPlayer"};
+      "Dav1dVideoDecoder",  "FuchsiaVideoDecoder",    "MediaPlayer",
+      "Gav1VideoDecoder"};
   printf("%18s = 0\n", "None");
   for (const auto& name : kDecoderNames)
-    printf("%18s = 0x%x\n", name.c_str(), base::PersistentHash(name));
+    printf("%18s = 0x%08x\n", name.c_str(), base::PersistentHash(name));
 }
 
 }  // namespace media