[Local Media Casting] Adding a metric to log the casted file's size

Bug: 721802
Change-Id: I592898445b73c36ed4744f7025e4613843b0c586
Reviewed-on: https://chromium-review.googlesource.com/570490
Commit-Queue: Anna Maria <paezagon@chromium.org>
Reviewed-by: Jennifer Apacible <apacible@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487284}

chrome/browser/media/router/media_router_metrics.cc

@@ -28,7 +28,9 @@ const char MediaRouterMetrics::kHistogramIconClickLocation[] =
 const char MediaRouterMetrics::kHistogramMediaRouterCastingSource[] =
     "MediaRouter.Source.CastingSource";
 const char MediaRouterMetrics::kHistogramMediaRouterFileFormat[] =
-    "MediaRouter.Source.FileFormat";
+    "MediaRouter.Source.LocalFileFormat";
+const char MediaRouterMetrics::kHistogramMediaRouterFileSize[] =
+    "MediaRouter.Source.LocalFileSize";
 const char MediaRouterMetrics::kHistogramRouteCreationOutcome[] =
     "MediaRouter.Route.CreationOutcome";
 const char MediaRouterMetrics::kHistogramUiDialogPaint[] =
@@ -91,6 +93,10 @@ void MediaRouterMetrics::RecordMediaRouterFileFormat(
                             media::container_names::CONTAINER_MAX);
 }
 
+void MediaRouterMetrics::RecordMediaRouterFileSize(int64_t size) {
+  UMA_HISTOGRAM_MEMORY_LARGE_MB(kHistogramMediaRouterFileSize, size);
+}
+
 void MediaRouterMetrics::RecordDialDeviceCounts(size_t available_device_count,
                                                 size_t known_device_count) {
   if (clock_->Now() - device_count_metrics_record_time_ <

chrome/browser/media/router/media_router_metrics.h

@@ -68,6 +68,7 @@ class MediaRouterMetrics {
   static const char kHistogramIconClickLocation[];
   static const char kHistogramMediaRouterCastingSource[];
   static const char kHistogramMediaRouterFileFormat[];
+  static const char kHistogramMediaRouterFileSize[];
   static const char kHistogramRouteCreationOutcome[];
   static const char kHistogramUiDialogPaint[];
   static const char kHistogramUiDialogLoadedWithData[];
@@ -103,6 +104,9 @@ class MediaRouterMetrics {
   static void RecordMediaRouterFileFormat(
       media::container_names::MediaContainerName format);
 
+  // Records the size of a cast file.
+  static void RecordMediaRouterFileSize(int64_t size);
+
   // Records device counts.
   // TODO(zhaobin): Move device count specific metrics and state into its own
   // class eventually.

chrome/browser/ui/webui/media_router/media_router_file_dialog.cc

@@ -154,7 +154,10 @@ void MediaRouterFileDialog::MaybeReportLastSelectedFileInformation() {
         base::BindOnce(&MediaRouterFileDialog::ReportFileFormat,
                        base::Unretained(this), selected_file_->local_path));
 
-    // TODO(paezagon): Report file media length.
+    cancelable_task_tracker_.PostTask(
+        task_runner_.get(), FROM_HERE,
+        base::BindOnce(&MediaRouterFileDialog::ReportFileSize,
+                       base::Unretained(this), selected_file_->local_path));
   } else {
     VLOG(1) << "MediaRouterFileDialog did not report file information; no file "
                "to report.";
@@ -187,6 +190,16 @@ void MediaRouterFileDialog::ReportFileFormat(const base::FilePath& filename) {
           reinterpret_cast<const uint8_t*>(buffer), read));
 }
 
+void MediaRouterFileDialog::ReportFileSize(const base::FilePath& filename) {
+  int64_t size;
+  if (base::GetFileSize(filename, &size)) {
+    MediaRouterMetrics::RecordMediaRouterFileSize(size);
+  } else {
+    VLOG(1) << "Can't get file size for file: " << filename.LossyDisplayName()
+            << ".";
+  }
+}
+
 void MediaRouterFileDialog::FileSelected(const base::FilePath& path,
                                          int index,
                                          void* params) {

chrome/browser/ui/webui/media_router/media_router_file_dialog.h

@@ -114,6 +114,9 @@ class MediaRouterFileDialog : public ui::SelectFileDialog::Listener {
   // Reports the format of a file to the UMA stats.
   void ReportFileFormat(const base::FilePath& filename);
 
+  // Reports the size of a file to the UMA stats.
+  void ReportFileSize(const base::FilePath& filename);
+
   // Overridden from SelectFileDialog::Listener:
   void FileSelected(const base::FilePath& path,
                     int index,

tools/metrics/histograms/histograms.xml

@@ -31686,7 +31686,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
-<histogram name="MediaRouter.Source.FileFormat" enum="MediaContainers">
+<histogram name="MediaRouter.Source.LocalFileFormat" enum="MediaContainers">
   <owner>paezagon@chromium.org</owner>
   <summary>
     The file format of a local media Media Router session. This is recorded when
@@ -31695,6 +31695,16 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="MediaRouter.Source.LocalFileSize" units="MB">
+  <owner>paezagon@chromium.org</owner>
+  <summary>
+    The file size of a local media Media Router session. This is recorded when a
+    casting session begins to keep track of what kind of media is being
+    streamed, specifically, whether it is a clip or a song, or a full length
+    film or podcast.
+  </summary>
+</histogram>
+
 <histogram name="MediaRouter.Ui.Action.CloseLatency" units="ms">
   <owner>apacible@chromium.org</owner>
   <summary>