• Support setting base::FeatureList with the experimental option "feature_list": { "enable-features": "...", "disable-features": "..." }. See comments of InitializeFromCommandLine in https://source.chromium.org/chromium/chromium/src/+/main:base/feature_list.h for details.
• Support setting the network isolation key of a stream with stream header -network-isolation-key. The header value should be a valid URL with different host and port for each different network isolation key. Network isolation takes effect only if it is enabled by experimental
  option of "feature_list": { "enable-features": "PartitionConnectionsByNetworkIsolationKey" }.