go/system: adding two-phase data pipe methods

mojo/public/go/system/c_allocators.c

Index: mojo/public/go/system/c_allocators.c
diff --git a/mojo/public/go/system/c_allocators.c b/mojo/public/go/system/c_allocators.c
index 7af7bb2f7dbba284afcf373ec1cfa3fd6089ccc1..2f93908be747e5e179aa9b7f654f0acd393eabb3 100644
--- a/mojo/public/go/system/c_allocators.c
+++ b/mojo/public/go/system/c_allocators.c
@@ -157,3 +157,15 @@ void FreeWriteDataParams(struct WriteDataParams p) {
   free(p.num_bytes);
   free(p.elements);
 }
+
+struct TwoPhaseActionParams MallocTwoPhaseActionParams() {
+  struct TwoPhaseActionParams p;
+  p.buffer = (void**)malloc(sizeof(void*));
+  p.num_bytes = (uint32_t*)malloc(sizeof(uint32_t));
+  return p;
+}
+
+void FreeTwoPhaseActionParams(struct TwoPhaseActionParams p) {
+  free(p.buffer);
+  free(p.num_bytes);
+}