Change the thread interface in runtime/platform and use it starting all threads

runtime/platform/thread.h

Index: runtime/platform/thread.h
diff --git a/runtime/platform/thread.h b/runtime/platform/thread.h
index 0eb8da13b2b502412cc21ac54951290785a4a64e..005c41e29e2873140b6c27e1e3e49c81fbfb7099 100644
--- a/runtime/platform/thread.h
+++ b/runtime/platform/thread.h
@@ -22,17 +22,15 @@ namespace dart {
 
 class Thread {
  public:
-  // Function to be called on thread start.
-  typedef void (*ThreadStartFunction) (uword parameter);
-
-  // TODO(iposva): Define the proper interface for spawning and killing threads.
-  Thread(ThreadStartFunction function, uword parameters);
-  ~Thread();
+  static const int64_t kNoTimeout = 0;
+  static const ThreadHandle kInvalidThreadHandle;
 
- private:
-  ThreadData data_;
+  typedef void (*ThreadStartFunction) (uword parameter);
 
-  DISALLOW_COPY_AND_ASSIGN(Thread);
+  // Start a thread running the specified function.
+  static ThreadHandle Start(ThreadStartFunction function, uword parameters);
+  // Wait for thread termination or timeout.
+  static void Join(ThreadHandle thread);

[Ivan Posva, 2012/01/20 16:45:55]

Please remove the Join functionality it is not really useful. That will also
remove the need for defining and returning a ThreadHandle.

[Søren Gjesse, 2012/01/23 13:14:58]

Why is Join not useful? Especially for testing I have found that if a test uses
a number of threads to do something then just joining with all the threads on
the main thread works nicely. Without Join some other synchronization mechanism
will be needed for that.

I missed that the pthreads created by to VM where detached by default whereas
the ones used by the eventhandler and thread pool here joinable (not using this
shared code before).

I have added a flag to Start for specified joinable - that might be an option.

 };