Add metrics for Remount failure in Native SMB File Share

This adds the metrics for the errors received during a failure in
Remount in Native SMB File Share

Bug: 757625
Change-Id: Ibb63eda818b0de190526b26e79a87288a13b67db
Reviewed-on: https://chromium-review.googlesource.com/1080209
Commit-Queue: Allen Vicencio <allenvic@chromium.org>
Reviewed-by: Brian White <bcwhite@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#564808}

chrome/browser/chromeos/smb_client/smb_service.cc

@@ -36,6 +36,11 @@ void RecordMountResult(SmbMountResult result) {
   UMA_HISTOGRAM_ENUMERATION("NativeSmbFileShare.MountResult", result);
 }
 
+void RecordRemountResult(SmbMountResult result) {
+  DCHECK_LE(result, SmbMountResult::kMaxValue);
+  UMA_HISTOGRAM_ENUMERATION("NativeSmbFileShare.RemountResult", result);
+}
+
 }  // namespace
 
 SmbService::SmbService(Profile* profile)
@@ -189,6 +194,8 @@ void SmbService::Remount(const ProvidedFileSystemInfo& file_system_info) {
 
 void SmbService::OnRemountResponse(const std::string& file_system_id,
                                    smbprovider::ErrorType error) {
+  RecordRemountResult(TranslateErrorToMountResult(error));
+
   if (error != smbprovider::ERROR_OK) {
     LOG(ERROR) << "SmbService: failed to restore filesystem: "
                << file_system_id;

tools/metrics/histograms/histograms.xml

@@ -44935,6 +44935,15 @@ uploading your change for review.
   </summary>
 </histogram>
 
+<histogram name="NativeSmbFileShare.RemountResult"
+    enum="NativeSmbFileShare_MountResult">
+  <owner>zentaro@chromium.org</owner>
+  <summary>
+    The result of the Remount operation during startup. This is recorded after
+    the D-Bus call to Remount returns.
+  </summary>
+</histogram>
+
 <histogram name="Navigation.BackForward.CacheFlags" enum="NavigationCacheEnum">
   <owner>clamy@chromium.org</owner>
   <summary>The cache flags set on back-forward navigations.</summary>