Add DriveFS to about:flags.

Also move the DriveFS feature to a more common location in
chromeos/chromeos_features.h.

Bug: 859800
Change-Id: Iffffea69c4874ae0583c67e8a8e6a9b50a4951e4
Reviewed-on: https://chromium-review.googlesource.com/1124211Reviewed-by: Stuart Langley <slangley@chromium.org>
Reviewed-by: Noel Gordon <noel@chromium.org>
Commit-Queue: Sam McNally <sammc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572459}

chrome/browser/about_flags.cc

@@ -4041,6 +4041,12 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kGamepadPollingRateDescription, kOsDesktop,
      MULTI_VALUE_TYPE(kGamepadPollingRateChoices)},
 
+#if defined(OS_CHROMEOS)
+    {"enable-drive-fs", flag_descriptions::kEnableDriveFsName,
+     flag_descriptions::kEnableDriveFsDescription, kOsCrOS,
+     FEATURE_VALUE_TYPE(chromeos::features::kDriveFs)},
+#endif  // OS_CHROMEOS
+
     // NOTE: Adding a new flag requires adding a corresponding entry to enum
     // "LoginCustomFlags" in tools/metrics/histograms/enums.xml. See "Flag
     // Histograms" in tools/metrics/histograms/README.md (run the

chrome/browser/chromeos/drive/drive_integration_service.cc

@@ -32,6 +32,7 @@
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
+#include "chromeos/chromeos_features.h"
 #include "components/drive/chromeos/file_cache.h"
 #include "components/drive/chromeos/file_system.h"
 #include "components/drive/chromeos/resource_metadata.h"
@@ -207,8 +208,6 @@ FileError InitializeMetadata(
 
 }  // namespace
 
-const base::Feature kDriveFs{"DriveFS", base::FEATURE_DISABLED_BY_DEFAULT};
-
 // Observes drive disable Preference's change.
 class DriveIntegrationService::PreferenceWatcher {
  public:
@@ -341,7 +340,7 @@ DriveIntegrationService::DriveIntegrationService(
                                 : util::GetCacheRootPath(profile)),
       preference_watcher_(preference_watcher),
       drivefs_holder_(
-          base::FeatureList::IsEnabled(kDriveFs)
+          base::FeatureList::IsEnabled(chromeos::features::kDriveFs)
               ? std::make_unique<DriveFsHolder>(
                     profile_,
                     base::BindRepeating(&DriveIntegrationService::

chrome/browser/chromeos/drive/drive_integration_service.h

@@ -54,8 +54,6 @@ class ResourceMetadata;
 class ResourceMetadataStorage;
 }  // namespace internal
 
-extern const base::Feature kDriveFs;
-
 // Interface for classes that need to observe events from
 // DriveIntegrationService.  All events are notified on UI thread.
 class DriveIntegrationServiceObserver {

chrome/browser/chromeos/extensions/file_manager/private_api_file_system.cc

@@ -31,6 +31,7 @@
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/extensions/api/file_manager_private.h"
 #include "chrome/common/extensions/api/file_manager_private_internal.h"
+#include "chromeos/chromeos_features.h"
 #include "chromeos/disks/disk_mount_manager.h"
 #include "components/drive/chromeos/file_system_interface.h"
 #include "components/drive/drive.pb.h"
@@ -460,7 +461,7 @@ bool FileManagerPrivateGetSizeStatsFunction::RunAsync() {
     return false;
 
   if (volume->type() == file_manager::VOLUME_TYPE_GOOGLE_DRIVE &&
-      !base::FeatureList::IsEnabled(drive::kDriveFs)) {
+      !base::FeatureList::IsEnabled(chromeos::features::kDriveFs)) {
     drive::FileSystemInterface* file_system =
         drive::util::GetFileSystemByProfile(GetProfile());
     if (!file_system) {

chrome/browser/chromeos/file_manager/file_manager_browsertest_base.cc

@@ -35,6 +35,7 @@
 #include "chrome/common/chrome_features.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
+#include "chromeos/chromeos_features.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/components/drivefs/drivefs_host.h"
 #include "chromeos/components/drivefs/fake_drivefs.h"
@@ -885,7 +886,7 @@ void FileManagerBrowserTestBase::SetUpCommandLine(
     enabled_features.emplace_back(features::kExperimentalCrostiniUI);
   }
   if (IsDriveFsTest()) {
-    enabled_features.emplace_back(drive::kDriveFs);
+    enabled_features.emplace_back(chromeos::features::kDriveFs);
   }
   feature_list_.InitWithFeatures(enabled_features, {});
 
@@ -1225,7 +1226,7 @@ void FileManagerBrowserTestBase::OnCommand(const std::string& name,
 
 drive::DriveIntegrationService*
 FileManagerBrowserTestBase::CreateDriveIntegrationService(Profile* profile) {
-  if (base::FeatureList::IsEnabled(drive::kDriveFs)) {
+  if (base::FeatureList::IsEnabled(chromeos::features::kDriveFs)) {
     drive_volumes_[profile->GetOriginalProfile()] =
         std::make_unique<DriveFsTestVolume>(profile->GetOriginalProfile());
   } else {

chrome/browser/flag_descriptions.cc

@@ -3001,6 +3001,10 @@ const char kEnableDragTabsInTabletModeName[] =
 const char kEnableDragTabsInTabletModeDescription[] =
     "Allows the user to drag the tabs out of a browser window in tablet mode.";
 
+const char kEnableDriveFsName[] = "Enable DriveFS";
+const char kEnableDriveFsDescription[] =
+    "Enables use of the new DriveFS-based Drive sync client.";
+
 const char kEnableEhvInputName[] =
     "Emoji, handwriting and voice input on opt-in IME menu";
 const char kEnableEhvInputDescription[] =

chrome/browser/flag_descriptions.h

@@ -1843,6 +1843,9 @@ extern const char kEnableDragAppsInTabletModeDescription[];
 extern const char kEnableDragTabsInTabletModeName[];
 extern const char kEnableDragTabsInTabletModeDescription[];
 
+extern const char kEnableDriveFsName[];
+extern const char kEnableDriveFsDescription[];
+
 extern const char kEnableEhvInputName[];
 extern const char kEnableEhvInputDescription[];
 

chromeos/chromeos_features.cc

@@ -12,6 +12,9 @@ namespace features {
 const base::Feature kAndroidMessagesIntegration{
     "AndroidMessagesIntegration", base::FEATURE_DISABLED_BY_DEFAULT};
 
+// If enabled, DriveFS will be used for Drive sync.
+const base::Feature kDriveFs{"DriveFS", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // If enabled, the Chrome OS Settings UI will include a menu for the unified
 // MultiDevice settings.
 const base::Feature kEnableUnifiedMultiDeviceSettings{

chromeos/chromeos_features.h

@@ -16,6 +16,7 @@ namespace features {
 // alongside the definition of their values in the .cc file.
 
 CHROMEOS_EXPORT extern const base::Feature kAndroidMessagesIntegration;
+CHROMEOS_EXPORT extern const base::Feature kDriveFs;
 CHROMEOS_EXPORT extern const base::Feature kEnableUnifiedMultiDeviceSettings;
 CHROMEOS_EXPORT extern const base::Feature kEnableUnifiedMultiDeviceSetup;
 

tools/metrics/histograms/enums.xml

@@ -27867,6 +27867,7 @@ from previous Chrome versions.
   <int value="-918900957" label="AutofillCreditCardAssist:disabled"/>
   <int value="-918618075" label="enable-service-worker"/>
   <int value="-914210146" label="enable-web-based-signin"/>
+  <int value="-913294939" label="DriveFS:enabled"/>
   <int value="-912456561" label="MidiManagerWinrt:enabled"/>
   <int value="-908421850" label="PointerEvent:enabled"/>
   <int value="-907234795" label="NewAudioRenderingMixingStrategy:disabled"/>
@@ -27959,6 +27960,7 @@ from previous Chrome versions.
   <int value="-746328467" label="ExpensiveBackgroundTimerThrottling:disabled"/>
   <int value="-744159181" label="disable-spdy-proxy-dev-auth-origin"/>
   <int value="-743103250" label="enable-linkable-ephemeral-apps"/>
+  <int value="-742469530" label="DriveFS:disabled"/>
   <int value="-741806604" label="DownloadsUi:disabled"/>
   <int value="-738957187" label="OmniboxUIExperimentSwapTitleAndUrl:disabled"/>
   <int value="-726892130" label="AndroidMessagesIntegration:disabled"/>