Remove HTML5 menu tag feature from experimental set

There are website compat issues with this feature on sites that use their
own <menuitem> tags (especially developer.apple.com).  Remove it from
the "experimental" set until there's a concrete plan in place to either
ship or resolve the issue to prevent ongoing issues for users running
with this flag enabled.

Note that you can always run chromium with
--enable-blink-features=ContextMenu in order to get this feature.

BUG=412945

Review-Url: https://codereview.chromium.org/2049093003
Cr-Commit-Position: refs/heads/master@{#398771}
diff --git a/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.in b/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.in
index aa90f95..4ff0ea9 100644
--- a/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.in
+++ b/third_party/WebKit/Source/platform/RuntimeEnabledFeatures.in
@@ -39,7 +39,7 @@
 ClientHints status=stable
 CompositedSelectionUpdate
 CompositorWorker status=experimental
-ContextMenu status=experimental
+ContextMenu status=test
 CorsRFC1918 status=test
 CredentialManager status=stable
 CSS3Text status=experimental