[netstack] ignore checksum offload capability

This capability was split into TX and RX upstream and renamed, so
removing it is needed to bump upstream without a breaking change. Since
we don't expose checksum offload, this is harmless.

Change-Id: I68853e21a4de2f484f950eb62d91f9ce3fff0982

src/connectivity/network/netstack/link/bridge/bridge.go

@@ -165,8 +165,8 @@ func (ep *Endpoint) SetPromiscuousMode(bool) error {
 // restrictive of the inputs.
 func CombineCapabilities(a, b stack.LinkEndpointCapabilities) stack.LinkEndpointCapabilities {
 	newCapabilities := a
-	// Take the minimum of CapabilityChecksumOffload and CapabilityLoopback.
-	newCapabilities &= b | ^(stack.CapabilityChecksumOffload | stack.CapabilityLoopback)
+	// Take the minimum of CapabilityLoopback.
+	newCapabilities &= b | ^(stack.CapabilityLoopback)
 	// Take the maximum of CapabilityResolutionRequired.
 	newCapabilities |= b & stack.CapabilityResolutionRequired
 	return newCapabilities
@@ -209,7 +209,7 @@ func (ep *Endpoint) DeliverNetworkPacket(rxEP stack.LinkEndpoint, srcLinkAddr, d
 	broadcast := false
 
 	switch dstLinkAddr {
-	case "\xff\xff\xff\xff\xff\xff":
+	case tcpip.LinkAddress([]byte{0xff, 0xff, 0xff, 0xff, 0xff, 0xff}):
 		broadcast = true
 	case ep.linkAddress:
 		ep.dispatcher.DeliverNetworkPacket(ep, srcLinkAddr, dstLinkAddr, p, vv)

src/connectivity/network/netstack/link/bridge/bridge_test.go

@@ -26,16 +26,16 @@ var (
 )
 
 func TestEndpointAttributes(t *testing.T) {
+	const zero = stack.LinkEndpointCapabilities(0)
+
 	resolutionRequired := stack.LinkEndpointCapabilities(stack.CapabilityResolutionRequired)
-	var resolutionNotRequired stack.LinkEndpointCapabilities
-	if bridge.CombineCapabilities(resolutionRequired, resolutionNotRequired) != resolutionRequired {
-		t.Errorf("got bridge.Combinecapabilities(%#v, %#v) == %#v, want == %#v", resolutionRequired, resolutionNotRequired, bridge.CombineCapabilities(resolutionRequired, resolutionNotRequired), resolutionRequired)
+	if got := bridge.CombineCapabilities(resolutionRequired, zero); got != resolutionRequired {
+		t.Errorf("got bridge.Combinecapabilities(%#v, %#v) == %#v, want == %#v", resolutionRequired, zero, got, resolutionRequired)
 	}
 
-	checksumAndLoopback := stack.LinkEndpointCapabilities(stack.CapabilityChecksumOffload | stack.CapabilityLoopback)
-	var noChecksumAndLoopback stack.LinkEndpointCapabilities
-	if bridge.CombineCapabilities(checksumAndLoopback, noChecksumAndLoopback) != noChecksumAndLoopback {
-		t.Errorf("got bridge.Combinecapabilities(%#v, %#v) == %#v, want == %#v", checksumAndLoopback, noChecksumAndLoopback, bridge.CombineCapabilities(checksumAndLoopback, noChecksumAndLoopback), noChecksumAndLoopback)
+	loopback := stack.LinkEndpointCapabilities(stack.CapabilityLoopback)
+	if got := bridge.CombineCapabilities(loopback, zero); got != zero {
+		t.Errorf("got bridge.Combinecapabilities(%#v, %#v) == %#v, want == %#v", loopback, zero, got, zero)
 	}
 
 	linkID1, _ := channel.New(1, 101, "")