Fixed pre-declarations of included types in generated code.

This was harmless, but unnecessary.

Change-Id: I1365a725e254d4ebbda081110a50277cb5118323
Tested: on Linux.

src/idl_gen_cpp.cpp

@@ -777,8 +777,10 @@ std::string GenerateCPP(const Parser &parser,
   for (auto it = parser.structs_.vec.begin();
        it != parser.structs_.vec.end(); ++it) {
     auto &struct_def = **it;
-    CheckNameSpace(struct_def, &code);
-    code += "struct " + struct_def.name + ";\n\n";
+    if (!struct_def.generated) {
+      CheckNameSpace(struct_def, &code);
+      code += "struct " + struct_def.name + ";\n\n";
+    }
   }
 
   // Generate code for all the enum declarations.

tests/monster_test_generated.h

@@ -5,14 +5,6 @@
 
 #include "flatbuffers/flatbuffers.h"
 
-namespace MyGame {
-namespace OtherNameSpace {
-
-struct Unused;
-
-}  // namespace OtherNameSpace
-}  // namespace MyGame
-
 namespace MyGame {
 namespace Example {