Add a Mojo EDK for Chrome that uses one OS pipe per message pipe.

mojo/runner/context.h

Index: mojo/runner/context.h
diff --git a/mojo/runner/context.h b/mojo/runner/context.h
index 5667385f3b3ad544e135b488de50ccd1838dff4f..edb116aff53e38a1e20215cae6a79282f076c767 100644
--- a/mojo/runner/context.h
+++ b/mojo/runner/context.h
@@ -11,12 +11,17 @@
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/time/time.h"
-#include "mojo/edk/embedder/process_delegate.h"
 #include "mojo/runner/scoped_user_data_dir.h"
 #include "mojo/runner/task_runners.h"
 #include "mojo/shell/application_manager.h"
 #include "url/gurl.h"
 
+#if defined(USE_CHROME_EDK)
+#include "mojo/edk/embedder/process_delegate.h"
+#else
+#include "third_party/mojo/src/mojo/edk/embedder/process_delegate.h"
+#endif
+
 namespace mojo {
 namespace package_manager {
 class PackageManagerImpl;