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android_webview / browser / aw_field_trials.cc [blame]
// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "android_webview/browser/aw_field_trials.h"
#include "android_webview/common/aw_features.h"
#include "android_webview/common/aw_switches.h"
#include "base/allocator/partition_alloc_features.h"
#include "base/base_paths_android.h"
#include "base/check.h"
#include "base/metrics/field_trial_params.h"
#include "base/metrics/persistent_histogram_allocator.h"
#include "base/path_service.h"
#include "components/history/core/browser/features.h"
#include "components/metrics/persistent_histograms.h"
#include "components/permissions/features.h"
#include "components/safe_browsing/core/common/features.h"
#include "components/translate/core/common/translate_util.h"
#include "components/viz/common/features.h"
#include "content/public/common/content_features.h"
#include "gpu/config/gpu_finch_features.h"
#include "media/base/media_switches.h"
#include "mojo/public/cpp/bindings/features.h"
#include "net/base/features.h"
#include "services/network/public/cpp/features.h"
#include "third_party/blink/public/common/features.h"
#include "third_party/blink/public/common/features_generated.h"
#include "ui/android/ui_android_features.h"
#include "ui/gl/gl_features.h"
namespace internal {
AwFeatureOverrides::AwFeatureOverrides(base::FeatureList& feature_list)
: feature_list_(feature_list) {}
AwFeatureOverrides::~AwFeatureOverrides() {
// TODO(crbug.com/379864779): This doesn't play well with potential server-
// side overrides.
for (const auto& field_trial_override : field_trial_overrides_) {
feature_list_->RegisterFieldTrialOverride(
field_trial_override.feature->name, field_trial_override.override_state,
field_trial_override.field_trial);
}
feature_list_->RegisterExtraFeatureOverrides(
std::move(overrides_), /*replace_use_default_overrides=*/true);
}
void AwFeatureOverrides::EnableFeature(const base::Feature& feature) {
overrides_.emplace_back(
std::cref(feature),
base::FeatureList::OverrideState::OVERRIDE_ENABLE_FEATURE);
}
void AwFeatureOverrides::DisableFeature(const base::Feature& feature) {
overrides_.emplace_back(
std::cref(feature),
base::FeatureList::OverrideState::OVERRIDE_DISABLE_FEATURE);
}
void AwFeatureOverrides::OverrideFeatureWithFieldTrial(
const base::Feature& feature,
base::FeatureList::OverrideState override_state,
base::FieldTrial* field_trial) {
field_trial_overrides_.emplace_back(FieldTrialOverride{
.feature = raw_ref(feature),
.override_state = override_state,
.field_trial = field_trial,
});
}
} // namespace internal
void AwFieldTrials::OnVariationsSetupComplete() {
// Persistent histograms must be enabled ASAP, but depends on Features.
base::FilePath metrics_dir;
if (base::PathService::Get(base::DIR_ANDROID_APP_DATA, &metrics_dir)) {
InstantiatePersistentHistogramsWithFeaturesAndCleanup(metrics_dir);
} else {
NOTREACHED();
}
}
// TODO(crbug.com/40271903): Consider to migrate all WebView feature overrides
// from the AwMainDelegate to the new mechanism here.
void AwFieldTrials::RegisterFeatureOverrides(base::FeatureList* feature_list) {
if (!feature_list) {
return;
}
internal::AwFeatureOverrides aw_feature_overrides(*feature_list);
// Disable third-party storage partitioning on WebView.
aw_feature_overrides.DisableFeature(
net::features::kThirdPartyStoragePartitioning);
// Disable the passthrough on WebView.
aw_feature_overrides.DisableFeature(
::features::kDefaultPassthroughCommandDecoder);
// HDR does not support webview yet. See crbug.com/1493153 for an explanation.
aw_feature_overrides.DisableFeature(ui::kAndroidHDR);
// Disable Reducing User Agent minor version on WebView.
aw_feature_overrides.DisableFeature(
blink::features::kReduceUserAgentMinorVersion);
// Disable fenced frames on WebView.
aw_feature_overrides.DisableFeature(blink::features::kFencedFrames);
// Disable FLEDGE on WebView.
aw_feature_overrides.DisableFeature(blink::features::kAdInterestGroupAPI);
aw_feature_overrides.DisableFeature(blink::features::kFledge);
// Disable low latency overlay for WebView. There is currently no plan to
// enable these optimizations in WebView though they are not fundamentally
// impossible.
aw_feature_overrides.DisableFeature(
blink::features::kLowLatencyCanvas2dImageChromium);
aw_feature_overrides.DisableFeature(
blink::features::kLowLatencyWebGLImageChromium);
// Disable Shared Storage on WebView.
aw_feature_overrides.DisableFeature(blink::features::kSharedStorageAPI);
// Disable scrollbar-color on WebView.
aw_feature_overrides.DisableFeature(blink::features::kScrollbarColor);
// Disable scrollbar-width on WebView.
aw_feature_overrides.DisableFeature(blink::features::kScrollbarWidth);
// Disable Populating the VisitedLinkDatabase on WebView.
aw_feature_overrides.DisableFeature(history::kPopulateVisitedLinkDatabase);
// WebView uses kWebViewVulkan to control vulkan. Pre-emptively disable
// kVulkan in case it becomes enabled by default.
aw_feature_overrides.DisableFeature(::features::kVulkan);
aw_feature_overrides.DisableFeature(::features::kWebPayments);
aw_feature_overrides.DisableFeature(::features::kServiceWorkerPaymentApps);
// WebView does not support overlay fullscreen yet for video overlays.
aw_feature_overrides.DisableFeature(media::kOverlayFullscreenVideo);
// WebView does not support EME persistent license yet, because it's not
// clear on how user can remove persistent media licenses from UI.
aw_feature_overrides.DisableFeature(media::kMediaDrmPersistentLicense);
// WebView does not support multiple processes, so don't try to call some
// MediaDrm APIs in a separate process.
aw_feature_overrides.DisableFeature(
media::kAllowMediaCodecCallsInSeparateProcess);
aw_feature_overrides.DisableFeature(::features::kBackgroundFetch);
// SurfaceControl is controlled by kWebViewSurfaceControl flag.
aw_feature_overrides.DisableFeature(::features::kAndroidSurfaceControl);
// TODO(crbug.com/40627649): WebOTP is not yet supported on
// WebView.
aw_feature_overrides.DisableFeature(::features::kWebOTP);
// TODO(crbug.com/40652382): WebXR is not yet supported on WebView.
aw_feature_overrides.DisableFeature(::features::kWebXr);
// TODO(crbug.com/40831925): Digital Goods API is not yet supported
// on WebView.
aw_feature_overrides.DisableFeature(::features::kDigitalGoodsApi);
aw_feature_overrides.DisableFeature(::features::kDynamicColorGamut);
// COOP is not supported on WebView yet. See:
// https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/XBKAGb2_7uAi.
aw_feature_overrides.DisableFeature(
network::features::kCrossOriginOpenerPolicy);
aw_feature_overrides.DisableFeature(::features::kInstalledApp);
aw_feature_overrides.DisableFeature(::features::kPeriodicBackgroundSync);
// Disabled until viz scheduling can be improved.
aw_feature_overrides.DisableFeature(
::features::kUseSurfaceLayerForVideoDefault);
// Disable dr-dc on webview.
aw_feature_overrides.DisableFeature(::features::kEnableDrDc);
// TODO(crbug.com/40703318): Web Bluetooth is not yet supported on WebView.
aw_feature_overrides.DisableFeature(::features::kWebBluetooth);
// TODO(crbug.com/41441927): WebUSB is not yet supported on WebView.
aw_feature_overrides.DisableFeature(::features::kWebUsb);
// Disable TFLite based language detection on webview until webview supports
// ML model delivery via Optimization Guide component.
// TODO(crbug.com/40819484): Enable the feature on Webview.
aw_feature_overrides.DisableFeature(
::translate::kTFLiteLanguageDetectionEnabled);
// Disable key pinning enforcement on webview.
aw_feature_overrides.DisableFeature(
net::features::kStaticKeyPinningEnforcement);
// FedCM is not yet supported on WebView.
aw_feature_overrides.DisableFeature(::features::kFedCm);
aw_feature_overrides.DisableFeature(
blink::features::kFedCmWithStorageAccessAPI);
// TODO(crbug.com/40272633): Web MIDI permission prompt for all usage.
aw_feature_overrides.DisableFeature(blink::features::kBlockMidiByDefault);
// Disable device posture API as the framework implementation causes
// AwContents to leak in apps that don't call destroy().
aw_feature_overrides.DisableFeature(blink::features::kDevicePosture);
aw_feature_overrides.DisableFeature(blink::features::kViewportSegments);
// PaintHolding for OOPIFs. This should be a no-op since WebView doesn't use
// site isolation but field trial testing doesn't indicate that. Revisit when
// enabling site isolation. See crbug.com/356170748.
aw_feature_overrides.DisableFeature(blink::features::kPaintHoldingForIframes);
// Since Default Nav Transition does not support WebView yet, disable the
// LocalSurfaceId increment flag. TODO(crbug.com/361600214): Re-enable for
// WebView when we start introducing this feature.
aw_feature_overrides.DisableFeature(
blink::features::kIncrementLocalSurfaceIdForMainframeSameDocNavigation);
// Disabling this feature for WebView, since it can switch focus when scrolled
// in cases with multiple views which can trigger HTML focus changes that
// aren't intended. See crbug.com/378779896, crbug.com/373672168 for more
// details.
aw_feature_overrides.DisableFeature(
::features::kFocusRenderWidgetHostViewAndroidOnActionDown);
if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kDebugBsa)) {
// Feature parameters can only be set via a field trial.
const char kTrialName[] = "StudyDebugBsa";
const char kGroupName[] = "GroupDebugBsa";
base::FieldTrial* field_trial =
base::FieldTrialList::CreateFieldTrial(kTrialName, kGroupName);
// If field_trial is null, there was some unexpected name conflict.
CHECK(field_trial);
base::FieldTrialParams params;
params.emplace(net::features::kIpPrivacyTokenServer.name,
"https://staging-phosphor-pa.sandbox.googleapis.com");
base::AssociateFieldTrialParams(kTrialName, kGroupName, params);
aw_feature_overrides.OverrideFeatureWithFieldTrial(
net::features::kEnableIpProtectionProxy,
base::FeatureList::OverrideState::OVERRIDE_ENABLE_FEATURE, field_trial);
aw_feature_overrides.EnableFeature(network::features::kMaskedDomainList);
}
// Feature parameters can only be set via a field trial.
// Note: Performing a field trial here means we cannot include
// |kDIPSTtl| in the testing config json.
{
const char kDipsWebViewExperiment[] = "DipsWebViewExperiment";
const char kDipsWebViewGroup[] = "DipsWebViewGroup";
base::FieldTrial* dips_field_trial = base::FieldTrialList::CreateFieldTrial(
kDipsWebViewExperiment, kDipsWebViewGroup);
CHECK(dips_field_trial) << "Unexpected name conflict.";
base::FieldTrialParams params;
const std::string ttl_time_delta_30_days = "30d";
params.emplace(features::kDIPSInteractionTtl.name, ttl_time_delta_30_days);
base::AssociateFieldTrialParams(kDipsWebViewExperiment, kDipsWebViewGroup,
params);
aw_feature_overrides.OverrideFeatureWithFieldTrial(
features::kDIPSTtl,
base::FeatureList::OverrideState::OVERRIDE_ENABLE_FEATURE,
dips_field_trial);
}
// Delete Incidental Party State (DIPS) feature is not yet supported on
// WebView.
aw_feature_overrides.DisableFeature(::features::kDIPS);
// These features have shown performance improvements in WebView but not some
// other platforms.
aw_feature_overrides.EnableFeature(features::kEnsureExistingRendererAlive);
aw_feature_overrides.EnableFeature(blink::features::kThreadedBodyLoader);
aw_feature_overrides.EnableFeature(blink::features::kThreadedPreloadScanner);
aw_feature_overrides.EnableFeature(blink::features::kPrecompileInlineScripts);
// This feature has not been experimented with yet on WebView.
// TODO(crbug.com/336852432): Enable this feature for WebView.
aw_feature_overrides.DisableFeature(
blink::features::kNavigationPredictorNewViewportFeatures);
// This feature is global for the process and thus should not be enabled by
// WebView.
aw_feature_overrides.DisableFeature(
base::features::kPartitionAllocMemoryTagging);
}