usb: Add separate flag for the device detector

Now that the new USB backend has been enabled by default on Windows we want to remove the old code path but there are still some rare issues which can be caused by Chrome enumerating USB devices. This flag should provide a workaround for those issues by not having USB enumeration running at all times while not requiring us to continue to support the old backend since the new one is overall better. Bug: 1041289,1167343,1239949 Change-Id: I45b864018a56f77bf0f241220a7fc553efa68742 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3183620 Commit-Queue: Reilly Grant <reillyg@chromium.org> Auto-Submit: Reilly Grant <reillyg@chromium.org> Reviewed-by: Scott Violet <sky@chromium.org> Cr-Commit-Position: refs/heads/main@{#924994}
blueboxd · Sep 25, 2021 · 3c560fa · 3c560fa
1 parent 118c41d
commit 3c560fa
Show file tree

Hide file tree

Showing 8 changed files with 32 additions and 7 deletions.
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
@@ -3315,6 +3315,10 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kWebBluetoothNewPermissionsBackendDescription,
      kOsAndroid | kOsDesktop,
      FEATURE_VALUE_TYPE(features::kWebBluetoothNewPermissionsBackend)},
+    {"enable-webusb-device-detection",
+     flag_descriptions::kWebUsbDeviceDetectionName,
+     flag_descriptions::kWebUsbDeviceDetectionDescription, kOsDesktop,
+     FEATURE_VALUE_TYPE(features::kWebUsbDeviceDetection)},
 #if defined(USE_AURA)
     {"overscroll-history-navigation",
      flag_descriptions::kOverscrollHistoryNavigationName,

diff --git a/chrome/browser/browser_features.cc b/chrome/browser/browser_features.cc
@@ -86,4 +86,9 @@ bool ShouldTriggerNetworkDataMigration() {
   return false;
 }
 
+// Enables runtime detection of USB devices which provide a WebUSB landing page
+// descriptor.
+const base::Feature kWebUsbDeviceDetection{"WebUsbDeviceDetection",
+                                           base::FEATURE_ENABLED_BY_DEFAULT};
+
 }  // namespace features
diff --git a/chrome/browser/browser_features.h b/chrome/browser/browser_features.h
@@ -48,6 +48,8 @@ extern const base::Feature kTriggerNetworkDataMigration;
 // determine whether data migration should occur or not.
 bool ShouldTriggerNetworkDataMigration();
 
+extern const base::Feature kWebUsbDeviceDetection;
+
 }  // namespace features
 
 #endif  // CHROME_BROWSER_BROWSER_FEATURES_H_
diff --git a/chrome/browser/flag-metadata.json b/chrome/browser/flag-metadata.json
@@ -2858,6 +2858,11 @@
     "owners": [ "mcasas", "chromeos-gfx-video@google.com" ],
     "expiry_milestone": 88
   },
+  {
+    "name": "enable-webusb-device-detection",
+    "owners": [ "reillyg", "deviceapi-team@google.com" ],
+    "expiry_milestone": 104
+  },
   {
     "name": "enable-windows-gaming-input-data-fetcher",
     "owners": [ "qiaye@microsoft.com" ],

diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
@@ -2804,6 +2804,13 @@ const char kWebrtcUseMinMaxVEADimensionsDescription[] =
     "When enabled, WebRTC will only use the Video Encode Accelerator for "
     "video resolutions inside those published as supported.";
 
+const char kWebUsbDeviceDetectionName[] =
+    "Automatic detection of WebUSB-compatible devices";
+const char kWebUsbDeviceDetectionDescription[] =
+    "When enabled, the user will be notified when a device which advertises "
+    "support for WebUSB is connected. Disable if problems with USB devices are "
+    "observed when the browser is running.";
+
 const char kWebXrForceRuntimeName[] = "Force WebXr Runtime";
 const char kWebXrForceRuntimeDescription[] =
     "Force the browser to use a particular runtime, even if it would not "

diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
@@ -1586,6 +1586,9 @@ extern const char kWebrtcSrtpAesGcmDescription[];
 extern const char kWebrtcUseMinMaxVEADimensionsName[];
 extern const char kWebrtcUseMinMaxVEADimensionsDescription[];
 
+extern const char kWebUsbDeviceDetectionName[];
+extern const char kWebUsbDeviceDetectionDescription[];
+
 extern const char kWebXrForceRuntimeName[];
 extern const char kWebXrForceRuntimeDescription[];
 

diff --git a/chrome/browser/usb/web_usb_detector.cc b/chrome/browser/usb/web_usb_detector.cc
@@ -13,6 +13,7 @@
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
+#include "chrome/browser/browser_features.h"
 #include "chrome/browser/net/referrer.h"
 #include "chrome/browser/notifications/system_notification_helper.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -28,7 +29,6 @@
 #include "components/vector_icons/vector_icons.h"
 #include "content/public/browser/device_service.h"
 #include "content/public/browser/web_contents.h"
-#include "device/base/features.h"
 #include "services/device/public/mojom/usb_device.mojom.h"
 #include "services/network/public/cpp/is_potentially_trustworthy.h"
 #include "third_party/abseil-cpp/absl/types/optional.h"
@@ -184,13 +184,10 @@ WebUsbDetector::WebUsbDetector() = default;
 WebUsbDetector::~WebUsbDetector() = default;
 
 void WebUsbDetector::Initialize() {
-#if defined(OS_WIN)
-  // The WebUSB device detector is disabled on Windows due to jank and hangs
-  // caused by enumerating devices. The new USB backend is designed to resolve
-  // these issues so enable it for testing. https://crbug.com/656702
-  if (!base::FeatureList::IsEnabled(device::kNewUsbBackend))
+  // The WebUSB device detector can be disabled if it causes trouble due to
+  // buggy devices and drivers.
+  if (!base::FeatureList::IsEnabled(features::kWebUsbDeviceDetection))
     return;
-#endif  // defined(OS_WIN)
 
   // Tests may set a fake manager.
   if (!device_manager_) {

diff --git a/tools/metrics/histograms/enums.xml b/tools/metrics/histograms/enums.xml
@@ -50086,6 +50086,7 @@ from previous Chrome versions.
   <int value="-15879016"
       label="OmniboxUIExperimentUnboldSuggestionText:disabled"/>
   <int value="-13918890" label="disable-download-notification"/>
+  <int value="-13180015" label="WebUsbDeviceDetection:disabled"/>
   <int value="-12225998" label="ShareButtonInTopToolbar:disabled"/>
   <int value="-11983392"
       label="MagnifierContinuousMouseFollowingModeSetting:enabled"/>
@@ -52410,6 +52411,7 @@ from previous Chrome versions.
   <int value="1803465156" label="enable-zero-suggest-most-visited"/>
   <int value="1803470125" label="SyncUSSSessions:enabled"/>
   <int value="1803914892" label="TemporaryUnexpireFlagsM76:enabled"/>
+  <int value="1806450300" label="WebUsbDeviceDetection:enabled"/>
   <int value="1807374811" label="CCTModuleCache:enabled"/>
   <int value="1809940714" label="SpeculativeLaunchServiceWorker:disabled"/>
   <int value="1810258949" label="DisplayLocking:enabled"/>