WebXR depth: rename feature descriptor & adjust samples

Change-Id: I87a6a19fba49d8d8719d189ea4be026eb36261bd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2425128Reviewed-by: Brandon Jones <bajones@chromium.org>
Commit-Queue: Piotr Bialecki <bialpio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809833}

third_party/blink/renderer/modules/xr/xr_system.cc

@@ -138,7 +138,7 @@ base::Optional<device::mojom::XRSessionFeature> StringToXRSessionFeature(
              feature_string == "plane-detection") {
     return device::mojom::XRSessionFeature::PLANE_DETECTION;
   } else if (RuntimeEnabledFeatures::WebXRDepthEnabled(context) &&
-             feature_string == "depth") {
+             feature_string == "depth-sensing") {
     return device::mojom::XRSessionFeature::DEPTH;
   }
 

third_party/webxr_test_pages/webxr-samples/proposals/phone-ar-depth-gpu.html

@@ -98,7 +98,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
         // Requests an immersive session with environment integration.
 
         let options = {
-          requiredFeatures: ['depth'],
+          requiredFeatures: ['depth-sensing'],
         };
 
         navigator.xr.requestSession('immersive-ar', options).then((session) => {

third_party/webxr_test_pages/webxr-samples/proposals/phone-ar-depth.html

@@ -99,7 +99,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
         // Requests an immersive session with environment integration.
 
         let options = {
-          requiredFeatures: ['depth'],
+          requiredFeatures: ['depth-sensing'],
         };
 
         navigator.xr.requestSession('immersive-ar', options).then((session) => {