network - make network controller internal network switching explicit

app/scripts/controllers/network.js

@@ -20,7 +20,6 @@ module.exports = class NetworkController extends EventEmitter {
     this._proxy = createEventEmitterProxy()
 
     this.on('networkDidChange', this.lookupNetwork)
-    this.providerStore.subscribe((state) => this._switchNetwork({ rpcUrl: state.rpcTarget }))
   }
 
   initializeProvider (_providerParams) {
@@ -64,6 +63,7 @@ module.exports = class NetworkController extends EventEmitter {
       type: 'rpc',
       rpcTarget: rpcUrl,
     })
+    this._switchNetwork({ rpcUrl })
   }
 
   getCurrentRpcAddress () {
@@ -79,6 +79,7 @@ module.exports = class NetworkController extends EventEmitter {
     const rpcTarget = this.getRpcAddressForType(type)
     assert(rpcTarget, `NetworkController - unknown rpc address for type "${type}"`)
     this.providerStore.updateState({ type, rpcTarget })
+    this._switchNetwork({ rpcUrl: rpcTarget })
   }
 
   getProviderConfig () {