mojo: Allow circular dependencies between structs

mojo/public/cpp/bindings/struct_ptr.h

Index: mojo/public/cpp/bindings/struct_ptr.h
diff --git a/mojo/public/cpp/bindings/struct_ptr.h b/mojo/public/cpp/bindings/struct_ptr.h
index 75a46bb6f9969c3aef60eacc801a35bcfabbfbcf..5d0836489aadfda523cae11266bbb0793057d270 100644
--- a/mojo/public/cpp/bindings/struct_ptr.h
+++ b/mojo/public/cpp/bindings/struct_ptr.h
@@ -7,6 +7,7 @@
 
 #include <new>
 
+#include "mojo/public/cpp/bindings/type_converter.h"
 #include "mojo/public/cpp/environment/logging.h"
 #include "mojo/public/cpp/system/macros.h"
 
@@ -29,7 +30,6 @@ class StructPtr {
   MOJO_MOVE_ONLY_TYPE_FOR_CPP_03(StructPtr, RValue);
 
  public:
-  typedef typename Struct::Data_ Data_;
 
   StructPtr() : ptr_(nullptr) {}
   ~StructPtr() { delete ptr_; }
@@ -98,7 +98,6 @@ class InlinedStructPtr {
   MOJO_MOVE_ONLY_TYPE_FOR_CPP_03(InlinedStructPtr, RValue);
 
  public:
-  typedef typename Struct::Data_ Data_;
 
   InlinedStructPtr() : is_null_(true) {}
   ~InlinedStructPtr() {}