Increase touch slop when entering/leaving VR

VR input devices behave like laser pointers, leading to movements with
lower precision as opposed to a mouse or a touchpad, due to natural
shakiness of users. This change increases the slop when on VR browsing,
as a factor of the platform's slop.

Bug: 860321
Change-Id: I47906921ab41e69b7bc4e427ebbd327ae8f7d9bf
Reviewed-on: https://chromium-review.googlesource.com/1134088
Commit-Queue: Aldo Culquicondor <acondor@chromium.org>
Reviewed-by: Timothy Dresser <tdresser@chromium.org>
Cr-Commit-Position: refs/heads/master@{#574957}

content/browser/renderer_host/render_widget_host_view_android.cc

@@ -1887,6 +1887,10 @@ void RenderWidgetHostViewAndroid::SetIsInVR(bool is_in_vr) {
   // TODO(crbug.com/851054): support touch selection handles in VR.
   SetTextHandlesHiddenInternal();
 
+  gesture_provider_.UpdateConfig(ui::GetGestureProviderConfig(
+      is_in_vr_ ? ui::GestureProviderConfigType::CURRENT_PLATFORM_VR
+                : ui::GestureProviderConfigType::CURRENT_PLATFORM));
+
   if (is_in_vr_ && controls_initialized_) {
     // TODO(mthiesse, https://crbug.com/825765): See the TODO in
     // RenderWidgetHostViewAndroid::OnFrameMetadataUpdated. RWHVA isn't

ui/events/gesture_detection/filtered_gesture_provider.cc

@@ -18,10 +18,16 @@ FilteredGestureProvider::FilteredGestureProvider(
     const GestureProvider::Config& config,
     GestureProviderClient* client)
     : client_(client),
-      gesture_provider_(config, this),
+      gesture_provider_(std::make_unique<GestureProvider>(config, this)),
       gesture_filter_(this),
       handling_event_(false),
-      any_touch_moved_beyond_slop_region_(false) {
+      any_touch_moved_beyond_slop_region_(false) {}
+
+FilteredGestureProvider::~FilteredGestureProvider() = default;
+
+void FilteredGestureProvider::UpdateConfig(
+    const GestureProvider::Config& config) {
+  gesture_provider_ = std::make_unique<ui::GestureProvider>(config, this);
 }
 
 FilteredGestureProvider::TouchHandlingResult
@@ -34,7 +40,7 @@ FilteredGestureProvider::OnTouchEvent(const MotionEvent& event) {
   if (event.GetAction() == MotionEvent::Action::DOWN)
     any_touch_moved_beyond_slop_region_ = false;
 
-  if (!gesture_provider_.OnTouchEvent(event))
+  if (!gesture_provider_->OnTouchEvent(event))
     return TouchHandlingResult();
 
   TouchDispositionGestureFilter::PacketResult filter_result =
@@ -59,25 +65,25 @@ void FilteredGestureProvider::OnTouchEventAck(
 }
 
 void FilteredGestureProvider::ResetDetection() {
-  gesture_provider_.ResetDetection();
+  gesture_provider_->ResetDetection();
 }
 
 void FilteredGestureProvider::SetMultiTouchZoomSupportEnabled(
     bool enabled) {
-  gesture_provider_.SetMultiTouchZoomSupportEnabled(enabled);
+  gesture_provider_->SetMultiTouchZoomSupportEnabled(enabled);
 }
 
 void FilteredGestureProvider::SetDoubleTapSupportForPlatformEnabled(
     bool enabled) {
-  gesture_provider_.SetDoubleTapSupportForPlatformEnabled(enabled);
+  gesture_provider_->SetDoubleTapSupportForPlatformEnabled(enabled);
 }
 
 void FilteredGestureProvider::SetDoubleTapSupportForPageEnabled(bool enabled) {
-  gesture_provider_.SetDoubleTapSupportForPageEnabled(enabled);
+  gesture_provider_->SetDoubleTapSupportForPageEnabled(enabled);
 }
 
 const ui::MotionEvent* FilteredGestureProvider::GetCurrentDownEvent() const {
-  return gesture_provider_.current_down_event();
+  return gesture_provider_->current_down_event();
 }
 
 void FilteredGestureProvider::OnGestureEvent(const GestureEventData& event) {

ui/events/gesture_detection/filtered_gesture_provider.h

@@ -6,6 +6,7 @@
 #define UI_EVENTS_GESTURE_DETECTION_FILTERED_GESTURE_PROVIDER_H_
 
 #include <stdint.h>
+#include <memory>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
@@ -25,6 +26,9 @@ class GESTURE_DETECTION_EXPORT FilteredGestureProvider
   // and allowed by the |gesture_filter_|.
   FilteredGestureProvider(const GestureProvider::Config& config,
                           GestureProviderClient* client);
+  ~FilteredGestureProvider() final;
+
+  void UpdateConfig(const GestureProvider::Config& config);
 
   struct TouchHandlingResult {
     TouchHandlingResult();
@@ -62,7 +66,7 @@ class GESTURE_DETECTION_EXPORT FilteredGestureProvider
 
   GestureProviderClient* const client_;
 
-  ui::GestureProvider gesture_provider_;
+  std::unique_ptr<ui::GestureProvider> gesture_provider_;
   ui::TouchDispositionGestureFilter gesture_filter_;
 
   bool handling_event_;

ui/events/gesture_detection/gesture_provider_config_helper.cc

@@ -10,6 +10,8 @@
 namespace ui {
 namespace {
 
+constexpr float kSlopScaleForVr = 3.0f;
+
 class GenericDesktopGestureConfiguration : public GestureConfiguration {
  public:
   // The default GestureConfiguration parameters are already tailored for a
@@ -72,6 +74,10 @@ GestureProvider::Config BuildGestureProviderConfig(
   return config;
 }
 
+void TuneGestureProviderConfigForVr(GestureProvider::Config* config) {
+  config->gesture_detector_config.touch_slop *= kSlopScaleForVr;
+}
+
 }  // namespace
 
 GestureProvider::Config GetGestureProviderConfig(
@@ -81,6 +87,10 @@ GestureProvider::Config GetGestureProviderConfig(
     case GestureProviderConfigType::CURRENT_PLATFORM:
       config = BuildGestureProviderConfig(*GestureConfiguration::GetInstance());
       break;
+    case GestureProviderConfigType::CURRENT_PLATFORM_VR:
+      config = BuildGestureProviderConfig(*GestureConfiguration::GetInstance());
+      TuneGestureProviderConfigForVr(&config);
+      break;
     case GestureProviderConfigType::GENERIC_DESKTOP:
       config = BuildGestureProviderConfig(GenericDesktopGestureConfiguration());
       break;

ui/events/gesture_detection/gesture_provider_config_helper.h

@@ -13,9 +13,10 @@
 namespace ui {
 
 enum class GestureProviderConfigType {
-  CURRENT_PLATFORM,  // Parameters tailored for the current platform.
-  GENERIC_DESKTOP,   // Parameters typical for a desktop machine.
-  GENERIC_MOBILE     // Parameters typical for a mobile device (phone/tablet).
+  CURRENT_PLATFORM,     // Parameters tailored for the current platform.
+  CURRENT_PLATFORM_VR,  // Parameters tailored for the current platform in VR.
+  GENERIC_DESKTOP,      // Parameters typical for a desktop machine.
+  GENERIC_MOBILE  // Parameters typical for a mobile device (phone/tablet).
 };
 
 GESTURE_DETECTION_EXPORT GestureProvider::Config GetGestureProviderConfig(