DGAPI: Disable DGAPI on WebLayer (merge to M101)

Prevents a crash in WebLayer due to the interface not being available.
Verified that this fixes the crash at head.

Merge approved in https://bugs.chromium.org/p/chromium/issues/detail?id=1313771#c8

(cherry picked from commit feaefbe)

Bug: 1313771
Change-Id: I02bc19336261616174e531cfd8317be8294e9c58
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3577853
Auto-Submit: Glen Robertson <glenrob@chromium.org>
Reviewed-by: Robbie McElrath <rmcelrath@chromium.org>
Commit-Queue: Robbie McElrath <rmcelrath@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#990491}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3583587
Cr-Commit-Position: refs/branch-heads/4951@{#731}
Cr-Branched-From: 27de622-refs/heads/main@{#982481}

weblayer/app/content_main_delegate_impl.cc

@@ -177,6 +177,8 @@ bool ContentMainDelegateImpl::BasicStartupComplete(int* exit_code) {
   };
 
   std::vector<base::Feature> disabled_features = {
+    // TODO(crbug.com/1313771): Support Digital Goods API.
+    ::features::kDigitalGoodsApi,
     // TODO(crbug.com/1091212): make Notification triggers work with
     // WebLayer.
     ::features::kNotificationTriggers,