Remove some unneeded media.AVDA histograms.

We no longer need this data and/or the historical data should be
sufficient if we need it in the future.

BUG=644396

Review-Url: https://chromiumcodereview.appspot.com/2447463002
Cr-Commit-Position: refs/heads/master@{#426970}

media/gpu/android_video_decode_accelerator.cc

@@ -111,16 +111,6 @@ constexpr base::TimeDelta IdleTimerTimeOut = base::TimeDelta::FromSeconds(1);
 // from breaking the pipeline, if we're about to be reset anyway.
 constexpr base::TimeDelta ErrorPostingDelay = base::TimeDelta::FromSeconds(2);
 
-// For RecordFormatChangedMetric.
-enum FormatChangedValue {
-  CodecInitialized = false,
-  MissingFormatChanged = true
-};
-
-inline void RecordFormatChangedMetric(FormatChangedValue value) {
-  UMA_HISTOGRAM_BOOLEAN("Media.AVDA.MissingFormatChanged", !!value);
-}
-
 }  // namespace
 
 static base::LazyInstance<AVDACodecAllocator>::Leaky g_avda_codec_allocator =
@@ -755,11 +745,8 @@ bool AndroidVideoDecodeAccelerator::DequeueOutput() {
   }
 
   if (!picturebuffers_requested_) {
-    // If, somehow, we get a decoded frame back before a FORMAT_CHANGED
-    // message, then we might not have any picture buffers to use.  This
-    // isn't supposed to happen (see EncodeDecodeTest.java#617).
-    // Log a metric to see how common this is.
-    RecordFormatChangedMetric(FormatChangedValue::MissingFormatChanged);
+    // In 0.01% of playbacks MediaCodec returns a frame before FORMAT_CHANGED.
+    // Occurs on JB and M. (See the Media.AVDA.MissingFormatChanged histogram.)
     media_codec_->ReleaseOutputBuffer(buf_index, false);
     POST_ERROR(PLATFORM_FAILURE, "Dequeued buffers before FORMAT_CHANGED.");
     return false;
@@ -1059,9 +1046,6 @@ void AndroidVideoDecodeAccelerator::OnCodecConfigured(
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(state_ == WAITING_FOR_CODEC || state_ == SURFACE_DESTROYED);
 
-  // Record one instance of the codec being initialized.
-  RecordFormatChangedMetric(FormatChangedValue::CodecInitialized);
-
   // If we are supposed to notify that initialization is complete, then do so
   // now.  Otherwise, this is a reconfiguration.
   if (deferred_initialization_pending_) {

media/gpu/avda_picture_buffer_manager.cc

@@ -136,14 +136,6 @@ gl::ScopedJavaSurface AVDAPictureBufferManager::Initialize(
   state_provider_ = state_provider;
   shared_state_ = new AVDASharedState();
 
-  bool using_virtual_context = false;
-  if (gl::GLContext* context = gl::GLContext::GetCurrent()) {
-    if (gl::GLShareGroup* share_group = context->share_group())
-      using_virtual_context =
-          !!share_group->GetSharedContext(gl::GLSurface::GetCurrent());
-  }
-  UMA_HISTOGRAM_BOOLEAN("Media.AVDA.VirtualContext", using_virtual_context);
-
   // Acquire the SurfaceView surface if given a valid id.
   if (surface_view_id != VideoDecodeAccelerator::Config::kNoSurfaceID) {
     return gpu::GpuSurfaceLookup::GetInstance()->AcquireJavaSurface(

tools/metrics/histograms/histograms.xml

@@ -23493,6 +23493,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <histogram name="Media.AVDA.MissingFormatChanged" enum="BooleanFormatChanged">
   <owner>liberato@chromium.org</owner>
+  <obsolete>
+    Deprecated 10/2016. No longer needed.
+  </obsolete>
   <summary>
     Number of times that AVDA stopped decoding because MediaCodec failed to
     provide a FORMAT_CHANGED message before sending decoded frames back.  True
@@ -23503,6 +23506,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <histogram name="Media.AVDA.NumAVDAInstances" units="AVDA instances">
   <owner>watk@chromium.org</owner>
+  <obsolete>
+    Deprecated 10/2016. No longer needed.
+  </obsolete>
   <summary>
     The number of concurrently running AndroidVideoDecodeAccelerators. Logged
     during each AVDA initialization.
@@ -23511,6 +23517,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <histogram name="Media.AVDA.VirtualContext" enum="BooleanVirtualContext">
   <owner>liberato@chromium.org</owner>
+  <obsolete>
+    Deprecated 10/2016. No longer needed.
+  </obsolete>
   <summary>
     Number of times that AVDA's deferred rendering encountered a virtual GL
     context.  True counts indicate virtual, false counts indicate not.