Fixed generation bug for ARM ABI.

Closes #351.

src/Generator/Generators/CSharp/CSharpTextTemplate.cs

@@ -2848,7 +2848,7 @@ namespace CppSharp.Generators.CSharp
             }
 
             if (!function.HasIndirectReturnTypeParameter &&
-                isInstanceMethod && Options.IsItaniumAbi)
+                isInstanceMethod && Options.IsItaniumLikeAbi)
                 @params.Add("global::System.IntPtr instance");
 
             foreach (var param in function.Parameters)
@@ -2861,7 +2861,7 @@ namespace CppSharp.Generators.CSharp
                 @params.Add(string.Format("{0} {1}", typeName, param.Name));
 
                 if (param.Kind == ParameterKind.IndirectReturnType &&
-                    isInstanceMethod && Options.IsItaniumAbi)
+                    isInstanceMethod && Options.IsItaniumLikeAbi)
                     @params.Add("global::System.IntPtr instance");
             }
 

src/Generator/Options.cs

@@ -64,7 +64,7 @@ namespace CppSharp
         public bool IgnoreParseWarnings;
         public bool IgnoreParseErrors;
 
-        public bool IsItaniumAbi { get { return Abi == CppAbi.Itanium; } }
+        public bool IsItaniumLikeAbi { get { return Abi == CppAbi.Itanium || Abi == CppAbi.ARM; } }
         public bool IsMicrosoftAbi { get { return Abi == CppAbi.Microsoft; } }
 
         // Library options