certain eviction scenarios, leading to dropped response headers.

## Version 1.5.1

_2014-03-11_

 * Fix 1.5.0 regression where connections should not have been recycled.
 * Fix 1.5.0 regression where transparent Gzip was broken by attempting to
   recover from another I/O failure.
 * Fix problems where spdy/3.1 headers may not have been compressed properly.

import okhttp3.internal.toImmutableList

/**
 * Selects routes to connect to an origin server. Each connection requires a choice of proxy server,
 * IP address, and TLS mode. Connections may also be recycled.
 */
class RouteSelector(
  private val address: Address,
  private val routeDatabase: RouteDatabase,
  private val connectionUser: ConnectionUser,
  private val fastFallback: Boolean,
) {