[Fuchsia] Enable UDPSocketTest.LocalBroadcast

This behaviour was fixed upstream.

Bug: fuchsia:20603
Fixed: 959314
Change-Id: Ida123b8d8d2ffb32adb56e19432cd64f8bad28d1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2421766Reviewed-by: Matt Mueller <mattm@chromium.org>
Commit-Queue: Tamir Duberstein <tamird@google.com>
Cr-Commit-Position: refs/heads/master@{#809130}

net/socket/udp_socket_unittest.cc

@@ -316,12 +316,11 @@ TEST_F(UDPSocketTest, PartialRecv) {
   EXPECT_EQ(second_packet, received);
 }
 
-#if defined(OS_APPLE) || defined(OS_ANDROID) || defined(OS_FUCHSIA)
+#if defined(OS_APPLE) || defined(OS_ANDROID)
 // - MacOS: requires root permissions on OSX 10.7+.
 // - Android: devices attached to testbots don't have default network, so
 // broadcasting to 255.255.255.255 returns error -109 (Address not reachable).
 // crbug.com/139144.
-// - Fuchsia: TODO(crbug.com/959314): broadcast support is not implemented yet.
 #define MAYBE_LocalBroadcast DISABLED_LocalBroadcast
 #else
 #define MAYBE_LocalBroadcast LocalBroadcast