Introduce a Gin class instead of using global functions to control gin

gin/test/run_all_unittests.cc

Index: gin/test/run_all_unittests.cc
diff --git a/gin/test/run_all_unittests.cc b/gin/test/run_all_unittests.cc
index c8644ed3ed6c9a5a5d38674aa4cf1eb716df58fe..cb1c96c7bf5440283d1f48ec49b352683db1a9d6 100644
--- a/gin/test/run_all_unittests.cc
+++ b/gin/test/run_all_unittests.cc
@@ -5,15 +5,13 @@
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/test/launcher/unit_test_launcher.h"
 #include "base/test/test_suite.h"
-#include "gin/initialize.h"
 
 int main(int argc, char** argv) {
   base::TestSuite test_suite(argc, argv);
 
-  gin::Initialize();
-
   return base::LaunchUnitTests(
       argc, argv, base::Bind(&base::TestSuite::Run,
                              base::Unretained(&test_suite)));