Download: Deprecate a parallel download metric.

Deprecate metric "Download.ParallelDownloadAddStreamSuccess".

Bug: 1127951
Change-Id: I534468866d00f42b00575c6143c282b05c3a2c0d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2485840Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Commit-Queue: Xing Liu <xingliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#818976}

components/download/internal/common/download_stats.cc

@@ -601,18 +601,6 @@ void RecordParallelDownloadRequestCount(int request_count) {
                               request_count, 1, 10, 11);
 }
 
-void RecordParallelDownloadAddStreamSuccess(bool success,
-                                            bool support_range_request) {
-  if (support_range_request) {
-    base::UmaHistogramBoolean("Download.ParallelDownloadAddStreamSuccess",
-                              success);
-  } else {
-    base::UmaHistogramBoolean(
-        "Download.ParallelDownloadAddStreamSuccess.NoAcceptRangesHeader",
-        success);
-  }
-}
-
 void RecordParallelRequestCreationFailure(DownloadInterruptReason reason) {
   base::UmaHistogramSparse("Download.ParallelDownload.CreationFailureReason",
                            reason);

components/download/internal/common/parallel_download_job.cc

@@ -34,7 +34,6 @@ ParallelDownloadJob::ParallelDownloadJob(
       content_length_(create_info.total_bytes),
       requests_sent_(false),
       is_canceled_(false),
-      range_support_(create_info.accept_range),
       url_loader_factory_provider_(std::move(url_loader_factory_provider)),
       wake_lock_provider_binder_(std::move(wake_lock_provider_binder)) {}
 
@@ -130,9 +129,6 @@ void ParallelDownloadJob::OnInputStreamReady(
   bool success =
       DownloadJob::AddInputStream(std::move(input_stream), worker->offset());
 
-  RecordParallelDownloadAddStreamSuccess(
-      success, range_support_ == RangeRequestSupportType::kSupport);
-
   // Destroy the request if the sink is gone.
   if (!success) {
     VLOG(kDownloadJobVerboseLevel)

components/download/internal/common/parallel_download_job.h

@@ -110,9 +110,6 @@ class COMPONENTS_DOWNLOAD_EXPORT ParallelDownloadJob
   // If the download progress is canceled.
   bool is_canceled_;
 
-  // Whether the server accepts range requests.
-  RangeRequestSupportType range_support_;
-
   // URLLoaderFactoryProvider to retrieve the URLLoaderFactory and issue
   // parallel requests.
   URLLoaderFactoryProvider::URLLoaderFactoryProviderPtr

components/download/public/common/download_stats.h

@@ -305,13 +305,6 @@ COMPONENTS_DOWNLOAD_EXPORT void RecordParallelizableDownloadCount(
 COMPONENTS_DOWNLOAD_EXPORT void RecordParallelDownloadRequestCount(
     int request_count);
 
-// Records if each byte stream is successfully added to download sink.
-// |support_range_request| indicates whether the server strongly supports range
-// requests.
-COMPONENTS_DOWNLOAD_EXPORT void RecordParallelDownloadAddStreamSuccess(
-    bool success,
-    bool support_range_request);
-
 // Records the bandwidth for parallelizable download and estimates the saved
 // time at the file end. Does not count in any hash computation or file
 // open/close time.

tools/metrics/histograms/histograms_xml/download/histograms.xml

@@ -514,6 +514,9 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 
 <histogram name="Download.ParallelDownloadAddStreamSuccess"
     enum="BooleanSuccess" expires_after="2020-10-25">
+  <obsolete>
+    Depcreated 10/2020
+  </obsolete>
   <owner>xingliu@chromium.org</owner>
   <summary>
     Records if the byte stream reader of a subsequent request is successfully

tools/metrics/histograms/histograms_xml/histogram_suffixes_list.xml

@@ -11264,6 +11264,9 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram_suffixes>
 
 <histogram_suffixes name="NoAcceptRangesHeader" separator=".">
+  <obsolete>
+    Deprecated 10/2020
+  </obsolete>
   <suffix name="NoAcceptRangesHeader"
       label="For parallel requests created without accept-ranges header."/>
   <affected-histogram name="Download.ParallelDownloadAddStreamSuccess"/>