Simplify mojo_shell since it's now only used for Mandoline.

mojo/application/application_runner_chromium.cc

Index: mojo/application/application_runner_chromium.cc
diff --git a/mojo/application/application_runner_chromium.cc b/mojo/application/application_runner_chromium.cc
index 069ff90e346b73affdf6a940c690ce63cb747a9e..cc15f1a7698a90e7e9e6cef00c470fa0b3cb5a2a 100644
--- a/mojo/application/application_runner_chromium.cc
+++ b/mojo/application/application_runner_chromium.cc
@@ -13,6 +13,18 @@
 #include "mojo/public/cpp/application/application_delegate.h"
 #include "mojo/public/cpp/application/application_impl.h"
 
+int g_argc;
+const char* const* g_argv;
+#if !defined(OS_WIN)
+extern "C" {
+__attribute__((visibility("default"))) void InitCommandLineArgs(
+    int argc, const char* const* argv) {
+  g_argc = argc;
+  g_argv = argv;
+}
+}
+#endif
+
 namespace mojo {
 
 // static
@@ -42,7 +54,7 @@ MojoResult ApplicationRunnerChromium::Run(
   DCHECK(!has_run_);
   has_run_ = true;
 
-  base::CommandLine::Init(0, NULL);
+  base::CommandLine::Init(g_argc, g_argv);
   base::AtExitManager at_exit;
 
 #ifndef NDEBUG