Disable PhysicalSocketTest.TestUdpReadyToSendIPv4 on Android.

The test didn't previously run on Android bots, but was enabled by
mistake in https://codereview.webrtc.org/1426643003/

It used to be long to the rtc_unittests target, which also don't run
on Android unfortunately. For now, let's just disable this one test
on Android to get the bots go green.

BUG=4364
TBR=pthatcher@webrtc.org

Review URL: https://codereview.webrtc.org/1419033007 .

Cr-Commit-Position: refs/heads/master@{#10464}
diff --git a/webrtc/base/physicalsocketserver_unittest.cc b/webrtc/base/physicalsocketserver_unittest.cc
index 6c7be9f..f2eabcd 100644
--- a/webrtc/base/physicalsocketserver_unittest.cc
+++ b/webrtc/base/physicalsocketserver_unittest.cc
@@ -215,8 +215,9 @@
 // https://code.google.com/p/webrtc/issues/detail?id=4958
 // TODO(deadbeef): Enable again once test is reimplemented to be unflaky.
 // Also disable for ASan.
+// Disabled on Android: https://code.google.com/p/webrtc/issues/detail?id=4364
 #if defined(THREAD_SANITIZER) || defined(MEMORY_SANITIZER) || \
-  defined(ADDRESS_SANITIZER)
+  defined(ADDRESS_SANITIZER) || defined(WEBRTC_ANDROID)
 #define MAYBE_TestUdpReadyToSendIPv4 DISABLED_TestUdpReadyToSendIPv4
 #else
 #define MAYBE_TestUdpReadyToSendIPv4 TestUdpReadyToSendIPv4