Allow Thread to initialize COM for Windows consumers who need it

base/threading/thread.cc

Index: base/threading/thread.cc
===================================================================
--- base/threading/thread.cc	(revision 163371)
+++ base/threading/thread.cc	(working copy)
@@ -11,6 +11,10 @@
 #include "base/threading/thread_restrictions.h"
 #include "base/synchronization/waitable_event.h"
 
+#if defined(OS_WIN)
+#include "base/win/scoped_com_initializer.h"
+#endif
+
 namespace base {
 
 namespace {
@@ -45,7 +49,11 @@
 };
 
 Thread::Thread(const char* name)
-    : started_(false),
+    :
+#if defined(OS_WIN)
+      com_status_(NONE),
+#endif
+      started_(false),
       stopping_(false),
       running_(false),
       startup_data_(NULL),
@@ -60,11 +68,20 @@
 }
 
 bool Thread::Start() {
-  return StartWithOptions(Options());
+  Options options;
+#if defined(OS_WIN)
+  if (com_status_ == STA)
+    options.message_loop_type = MessageLoop::TYPE_UI;
+#endif
+  return StartWithOptions(options);
 }
 
 bool Thread::StartWithOptions(const Options& options) {
   DCHECK(!message_loop_);
+#if defined(OS_WIN)
+  DCHECK((com_status_ != STA) ||
+      (options.message_loop_type == MessageLoop::TYPE_UI));
+#endif
 
   SetThreadWasQuitProperly(false);
 
@@ -90,7 +107,7 @@
 }
 
 void Thread::Stop() {
-  if (!thread_was_started())
+  if (!started_)
     return;
 
   StopSoon();
@@ -157,6 +174,15 @@
     message_loop.set_thread_name(name_);
     message_loop_ = &message_loop;
 
+#if defined(OS_WIN)
+    scoped_ptr<win::ScopedCOMInitializer> com_initializer;
+    if (com_status_ != NONE) {
+      com_initializer.reset((com_status_ == STA) ?
+          new win::ScopedCOMInitializer() :
+          new win::ScopedCOMInitializer(win::ScopedCOMInitializer::kMTA));
+    }
+#endif
+
     // Let the thread do extra initialization.
     // Let's do this before signaling we are started.
     Init();
@@ -172,6 +198,10 @@
     // Let the thread do extra cleanup.
     CleanUp();
 
+#if defined(OS_WIN)
+    com_initializer.reset();
+#endif
+
     // Assert that MessageLoop::Quit was called by ThreadQuitHelper.
     DCHECK(GetThreadWasQuitProperly());