mus Window Server: implement event capture

components/mus/ws/default_access_policy.cc

Index: components/mus/ws/default_access_policy.cc
diff --git a/components/mus/ws/default_access_policy.cc b/components/mus/ws/default_access_policy.cc
index ae4b8272eb68d1bcc95246763077df521398f3d9..615b8dca7ffcc8488f367f7452f448ab27c5a6a6 100644
--- a/components/mus/ws/default_access_policy.cc
+++ b/components/mus/ws/default_access_policy.cc
@@ -123,6 +123,11 @@ bool DefaultAccessPolicy::CanSetWindowTextInputState(
          delegate_->HasRootForAccessPolicy(window);
 }
 
+bool DefaultAccessPolicy::CanSetCapture(const ServerWindow* window) const {
+  return WasCreatedByThisConnection(window) ||
+         delegate_->HasRootForAccessPolicy(window);
+}
+
 bool DefaultAccessPolicy::CanSetFocus(const ServerWindow* window) const {
   return WasCreatedByThisConnection(window) ||
          delegate_->HasRootForAccessPolicy(window);