Refactor rtc_unittests into several targets.

webrtc/base/win32window_unittest.cc

Index: webrtc/base/win32window_unittest.cc
diff --git a/webrtc/base/win32window_unittest.cc b/webrtc/base/win32window_unittest.cc
index 5dba67eb520de4635e8b7c851009be2b5fd48a12..1819f924e96056d4c0d52f4b859294246df7802f 100644
--- a/webrtc/base/win32window_unittest.cc
+++ b/webrtc/base/win32window_unittest.cc
@@ -45,9 +45,9 @@ TEST(Win32WindowTest, Basics) {
   EXPECT_TRUE(wnd.Create(0, L"Test", 0, 0, 0, 0, 100, 100));
   EXPECT_TRUE(wnd.handle() != NULL);
   EXPECT_EQ(kDummyResult, ::SendMessage(wnd.handle(), WM_USER, 1, 2));
-  EXPECT_EQ(WM_USER, wnd.msg().message);
-  EXPECT_EQ(1, wnd.msg().wParam);
-  EXPECT_EQ(2, wnd.msg().lParam);
+  EXPECT_EQ(static_cast<UINT>(WM_USER), wnd.msg().message);
+  EXPECT_EQ(1u, wnd.msg().wParam);
+  EXPECT_EQ(2l, wnd.msg().lParam);
   wnd.Destroy();
   EXPECT_TRUE(wnd.handle() == NULL);
   EXPECT_TRUE(wnd.destroyed());