Add a histogram: Media.AVDA.NumAVDAInstances

media/gpu/android_video_decode_accelerator.cc

Index: media/gpu/android_video_decode_accelerator.cc
diff --git a/media/gpu/android_video_decode_accelerator.cc b/media/gpu/android_video_decode_accelerator.cc
index 41b1f28fec18d1a78bd58ff270103c8fa361966c..0455ff6db7a6fe30eee5f7ddfe3686b29f945b04 100644
--- a/media/gpu/android_video_decode_accelerator.cc
+++ b/media/gpu/android_video_decode_accelerator.cc
@@ -194,6 +194,9 @@ class AVDATimerManager {
     }
 
     thread_avda_instances_.insert(avda_instance);
+    UMA_HISTOGRAM_ENUMERATION("Media.AVDA.NumAVDAInstances",
+                              thread_avda_instances_.size(),
+                              31);  // PRESUBMIT_IGNORE_UMA_MAX
     return true;
   }