Adds the ability for MessageLoop to take a MessagePump

Using default args is against style guide, but there are a ton of
places (mostly tests) that define a MessageLoop as a member. I'll see
about a cleanup pass that removes the default args.

BUG=none
TEST=NONE
R=darin@chromium.org

Review URL: https://codereview.chromium.org/61643006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233800 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 39 insertions, 6 deletions

diff --git a/base/threading/thread.cc b/base/threading/thread.cc
index aca4ddb..ae4d373 100644
--- a/base/threading/thread.cc
+++ b/base/threading/thread.cc
@@ -49,6 +49,20 @@ struct Thread::StartupData {
         event(false, false) {}
 };
 
+Thread::Options::Options()
+    : message_loop_type(MessageLoop::TYPE_DEFAULT),
+      stack_size(0) {
+}
+
+Thread::Options::Options(MessageLoop::Type type,
+                         size_t size)
+    : message_loop_type(type),
+      stack_size(size) {
+}
+
+Thread::Options::~Options() {
+}
+
 Thread::Thread(const char* name)
     :
 #if defined(OS_WIN)
@@ -174,8 +188,14 @@ void Thread::ThreadMain() {
   {
     // The message loop for this thread.
     // Allocated on the heap to centralize any leak reports at this line.
-    scoped_ptr<MessageLoop> message_loop(
-        new MessageLoop(startup_data_->options.message_loop_type));
+    scoped_ptr<MessageLoop> message_loop;
+    if (!startup_data_->options.message_pump_factory.is_null()) {
+      message_loop.reset(
+          new MessageLoop(startup_data_->options.message_pump_factory.Run()));
+    } else {
+      message_loop.reset(
+          new MessageLoop(startup_data_->options.message_loop_type));
+    }
 
     // Complete the initialization of our Thread object.
     thread_id_ = PlatformThread::CurrentId();
diff --git a/base/threading/thread.h b/base/threading/thread.h
index 98831b8..99f9dd4 100644
--- a/base/threading/thread.h
+++ b/base/threading/thread.h
@@ -8,12 +8,16 @@
 #include <string>
 
 #include "base/base_export.h"
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/message_loop/message_loop_proxy.h"
 #include "base/threading/platform_thread.h"
 
 namespace base {
 
+class MessagePump;
+
 // A simple thread abstraction that establishes a MessageLoop on a new thread.
 // The consumer uses the MessageLoop of the thread to cause code to execute on
 // the thread.  When this object is destroyed the thread is terminated.  All
@@ -29,14 +33,23 @@ namespace base {
 //  (3.b)    MessageLoop::DestructionObserver::WillDestroyCurrentMessageLoop
 class BASE_EXPORT Thread : PlatformThread::Delegate {
  public:
-  struct Options {
-    Options() : message_loop_type(MessageLoop::TYPE_DEFAULT), stack_size(0) {}
-    Options(MessageLoop::Type type, size_t size)
-        : message_loop_type(type), stack_size(size) {}
+  struct BASE_EXPORT Options {
+    typedef Callback<scoped_ptr<MessagePump>()> MessagePumpFactory;
+
+    Options();
+    Options(MessageLoop::Type type, size_t size);
+    ~Options();
 
     // Specifies the type of message loop that will be allocated on the thread.
+    // This is ignored if message_pump_factory.is_null() is false.
     MessageLoop::Type message_loop_type;
 
+    // Used to create the MessagePump for the MessageLoop. The callback is Run()
+    // on the thread. If message_pump_factory.is_null(), then a MessagePump
+    // appropriate for |message_loop_type| is created. Setting this forces the
+    // MessageLoop::Type to TYPE_CUSTOM.
+    MessagePumpFactory message_pump_factory;
+
     // Specifies the maximum stack size that the thread is allowed to use.
     // This does not necessarily correspond to the thread's initial stack size.
     // A value of 0 indicates that the default maximum should be used.