Remove thread id from ThreadWrapper::Start().

Removes ThreadPosix::InitParams and a corresponding wait for an event.
This unblocks ThreadPosix::Start which had to wait for thread scheduling
for an event to trigger on the spawned thread, giving faster Start()
calls.

BUG=4413
R=tommi@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/43699004

Cr-Commit-Position: refs/heads/master@{#8709}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8709 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/system_wrappers/source/critical_section_unittest.cc b/webrtc/system_wrappers/source/critical_section_unittest.cc
index d876b13..b291d39 100644
--- a/webrtc/system_wrappers/source/critical_section_unittest.cc
+++ b/webrtc/system_wrappers/source/critical_section_unittest.cc
@@ -80,9 +80,8 @@
   ProtectedCount count(crit_sect);
   ThreadWrapper* thread = ThreadWrapper::CreateThread(
       &LockUnlockThenStopRunFunction, &count);
-  unsigned int id = 42;
   crit_sect->Enter();
-  ASSERT_TRUE(thread->Start(id));
+  ASSERT_TRUE(thread->Start());
   SwitchProcess();
   // The critical section is of reentrant mode, so this should not release
   // the lock, even though count.Count() locks and unlocks the critical section
@@ -109,9 +108,8 @@
   ProtectedCount count(crit_sect);
   ThreadWrapper* thread = ThreadWrapper::CreateThread(&LockUnlockRunFunction,
                                                       &count);
-  unsigned int id = 42;
   crit_sect->Enter();  // Make sure counter stays 0 until we wait for it.
-  ASSERT_TRUE(thread->Start(id));
+  ASSERT_TRUE(thread->Start());
   crit_sect->Leave();
 
   // The thread is capable of grabbing the lock multiple times,