Fix for DCHECK failure at startup of gin_shell.

gin/shell/gin_main.cc

Index: gin/shell/gin_main.cc
diff --git a/gin/shell/gin_main.cc b/gin/shell/gin_main.cc
index 62143c9926f5a609ff95c2c3ef593a351df4925f..ceb4d64f9a5c7a7f22b45b6dab5406f0658cc1e0 100644
--- a/gin/shell/gin_main.cc
+++ b/gin/shell/gin_main.cc
@@ -64,11 +64,12 @@ int main(int argc, char** argv) {
   gin::V8Initializer::LoadV8Snapshot();
 #endif
 
+  base::MessageLoop message_loop;
+
   gin::IsolateHolder::Initialize(gin::IsolateHolder::kStrictMode,
                                  gin::ArrayBufferAllocator::SharedInstance());
   gin::IsolateHolder instance;
 
-  base::MessageLoop message_loop;
 
   gin::GinShellRunnerDelegate delegate;
   gin::ShellRunner runner(&delegate, instance.isolate());