Implemented gamepad for generic-hand-select-grasp per the input profile

definition.

https://github.com/immersive-web/webxr-input-profiles/blob/master/packages/registry/profiles/generic/generic-hand-select-grasp.json

The grasp type exposes it as the correct button and does not trigger
the squeeze events.

Change-Id: I5041633e39f7f6b9bbc86bd379be64eeadc1055c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2628888Reviewed-by: Alexander Cooper <alcooper@chromium.org>
Commit-Queue: Lachlan Ford <laford@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#843686}

device/vr/openxr/openxr_controller.cc

@@ -110,6 +110,7 @@ XrResult OpenXrController::InitializeControllerActions() {
   RETURN_IF_XR_FAILED(CreateActionsForButton(OpenXrButtonType::kThumbrest));
   RETURN_IF_XR_FAILED(CreateActionsForButton(OpenXrButtonType::kButton1));
   RETURN_IF_XR_FAILED(CreateActionsForButton(OpenXrButtonType::kButton2));
+  RETURN_IF_XR_FAILED(CreateActionsForButton(OpenXrButtonType::kGrasp));
 
   const std::string type_string = GetStringFromType(type_);
   const std::string name_prefix = type_string + "_controller_";
@@ -415,6 +416,9 @@ XrResult OpenXrController::CreateActionsForButton(
     case OpenXrButtonType::kButton2:
       name_prefix += "lower_button_";
       break;
+    case OpenXrButtonType::kGrasp:
+      name_prefix += "grasp_";
+      break;
   }
 
   std::unordered_map<OpenXrButtonActionType, XrAction>& cur_button =

device/vr/openxr/openxr_input_helper.cc

@@ -89,6 +89,11 @@ base::Optional<Gamepad> GetXrStandardGamepad(
   if (thumbrest_button)
     builder.AddOptionalButtonData(thumbrest_button.value());
 
+  base::Optional<GamepadButton> grasp_button =
+      controller.GetButton(OpenXrButtonType::kGrasp);
+  if (grasp_button)
+    builder.AddOptionalButtonData(grasp_button.value());
+
   return builder.GetGamepad();
 }
 

device/vr/openxr/openxr_interaction_profiles.h

@@ -40,7 +40,8 @@ enum class OpenXrButtonType {
   kThumbrest = 4,
   kButton1 = 5,
   kButton2 = 6,
-  kMaxValue = 6,
+  kGrasp = 7,
+  kMaxValue = 7,
 };
 
 enum class OpenXrAxisType {
@@ -284,7 +285,7 @@ constexpr OpenXrButtonPathMap kGenericHandSelectGraspButtonPathMaps[] = {
      {{OpenXrButtonActionType::kPress, "/input/select/value"},
       {OpenXrButtonActionType::kValue, "/input/select/value"}},
      2},
-    {OpenXrButtonType::kTrigger,
+    {OpenXrButtonType::kGrasp,
      {{OpenXrButtonActionType::kPress, "/input/squeeze/value"},
       {OpenXrButtonActionType::kValue, "/input/squeeze/value"}},
      2},
@@ -416,7 +417,7 @@ constexpr OpenXrControllerInteractionProfile
         OpenXrInteractionProfileType::kHandSelectGrasp,
         "/interaction_profiles/microsoft/hand_interaction",
         kMSFTHandInteractionExtensionName,
-        GamepadMapping::kNone,
+        GamepadMapping::kXrStandard,
         kGenericHandSelectGraspInputProfile,
         base::size(kGenericHandSelectGraspInputProfile),
         kGenericHandSelectGraspButtonPathMaps,