Remove unused Media.PreloadMetadataSuspendWasIdeal histograms.

These are no longer useful since this features is on by default.

Fixed: 1053019
Change-Id: Ibb579ecd5dacf6bc168c95e50dd47362c3c4cc66
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2125430
Auto-Submit: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#754742}

media/blink/webmediaplayer_impl.cc

@@ -1622,18 +1622,6 @@ void WebMediaPlayerImpl::OnPipelineSeeked(bool time_updated) {
     // has been told about the ReadyState change.
     OnBufferingStateChangeInternal(BUFFERING_HAVE_ENOUGH,
                                    BUFFERING_CHANGE_REASON_UNKNOWN, true);
-
-    // If |skip_metrics_due_to_startup_suspend_| is unset by a resume started by
-    // the OnBufferingStateChangeInternal() call, record a histogram of it here.
-    //
-    // If the value is unset, that means we should not have suspended and we've
-    // likely incurred some cost to TimeToFirstFrame and TimeToPlayReady which
-    // will be reflected in those statistics.
-    base::UmaHistogramBoolean(
-        std::string("Media.PreloadMetadataSuspendWasIdeal.") +
-            ((HasVideo() && HasAudio()) ? "AudioVideo"
-                                        : (HasVideo() ? "Video" : "Audio")),
-        skip_metrics_due_to_startup_suspend_);
   }
 
   attempting_suspended_start_ = false;

tools/metrics/histograms/histograms.xml

@@ -74735,6 +74735,9 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 
 <histogram name="Media.PreloadMetadataSuspendWasIdeal" enum="Boolean"
     expires_after="M82">
+  <obsolete>
+    Removed 03/2020 in https://crbug.com/1053019.
+  </obsolete>
   <owner>media-dev@chromium.org</owner>
   <summary>
     Indicates if a suspend initiated for preload=metadata was ideal. I.e. we did
@@ -200835,6 +200838,9 @@ regressions. -->
 </histogram_suffixes>
 
 <histogram_suffixes name="WebMediaPlayerContentTypes" separator=".">
+  <obsolete>
+    Removed 03/2020 in https://crbug.com/1053019.
+  </obsolete>
   <suffix name="Audio" label=""/>
   <suffix name="AudioVideo" label=""/>
   <suffix name="Video" label=""/>