Implement pthread_rwlock functions for NaCl newlib

tests/threads/nacl.scons

 # -*- python -*-
 # Copyright (c) 2011 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 Import('env')
 
 # NOTE: the arm emulator does not handle atomic ops properly
 # NOTE: the default setting of 10k rounds is too slow on ARM
 EXTRA_ARGS = ['100']
@@ skipping 132 matching lines @@
     EXTRA_LIBS=['${PTHREAD_LIBS}', '${NONIRT_LIBS}'])
 
 node = env.CommandSelLdrTestNacl(
     'mutex_timedlock_test.out',
     mutex_timedlock_test_nexe
     )
 env.AddNodeToTestSuite(node, ['small_tests'], 'run_mutex_timedlock_test',
                        is_broken=env.IsRunningUnderValgrind() or
                                  env.UsingEmulator())
 
+rwlock_test_nexe = env.ComponentProgram(
+    'rwlock_test',
+    ['rwlock_test.c'],
+    EXTRA_LIBS=['${PTHREAD_LIBS}', '${NONIRT_LIBS}'])
+
+node = env.CommandSelLdrTestNacl(
+    'rwlock_test.out',
+    rwlock_test_nexe
+    )
+env.AddNodeToTestSuite(node, ['small_tests'], 'run_rwlock_test',
+                       is_broken=env.IsRunningUnderValgrind() or
+                                 env.UsingEmulator())
+
 thread_stack_test_nexe = env.ComponentProgram('thread_stack_test',
                                               'thread_stack_test.c',
                                               EXTRA_LIBS=['${PTHREAD_LIBS}',
                                                           '${NONIRT_LIBS}'])
 
 node = env.CommandSelLdrTestNacl(
     'thread_stack_test.out',
     thread_stack_test_nexe,
     size='small',
     )
@@ skipping 88 matching lines @@
 
 # This tests an interface that is provided by nacl-newlib but not nacl-glibc.
 if not env.Bit('nacl_glibc'):
   stack_end_test_nexe = env.ComponentProgram(
       'stack_end_test', ['stack_end_test.c'],
       EXTRA_LIBS=['${PTHREAD_LIBS}', '${NONIRT_LIBS}'])
 
   node = env.CommandSelLdrTestNacl('stack_end_test.out',
                                    stack_end_test_nexe)
   env.AddNodeToTestSuite(node, ['small_tests'], 'run_stack_end_test')