C bindings: Implement _Validate(), and some pre-requisites

mojom/generators/c/templates/interface.tmpl.go

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package templates
 
 const GenerateInterfaceDeclarations = `
 {{- /* . (dot) refers to the Go type |cgen.InterfaceTemplate| */ -}}
 {{define "GenerateInterfaceDeclarations" -}}
 {{- $interface := . -}}
@@ skipping 12 matching lines @@
 {{end}}
 
 {{range $message := $interface.Messages -}}
 // Message: {{$message.Name}}
 
 #define {{$interface.Name}}_{{$message.Name}}__Ordinal \
     ((uint32_t){{$message.MessageOrdinal}})
 #define {{$interface.Name}}_{{$message.Name}}__MinVersion \
     ((uint32_t){{$message.MinVersion}})
 
-
 struct {{$message.RequestStruct.Name}};
 {{template "GenerateStructDeclarations" $message.RequestStruct}}
 {{if ne $message.ResponseStruct.Name "" -}}
-#define {{$interface.Name}}_{{$message.Name}}__HasResponse 1
 struct {{$message.ResponseStruct.Name}};
 {{template "GenerateStructDeclarations" $message.ResponseStruct}}
-{{else}}
-#define {{$interface.Name}}_{{$message.Name}}__HasResponse 0
 {{end}}
 {{end}}
 {{end}}
 `
 
 const GenerateInterfaceDefinitions = `
 {{- /* . (dot) refers to the Go type |cgen.InterfaceTemplate| */ -}}
 {{define "GenerateInterfaceDefinitions" -}}
 {{- $interface := . -}}
 {{range $const := $interface.Constants -}}
 const {{$const.Type}} {{$const.Name}} = {{$const.Value}};
 {{end -}}
 
 // Interface message struct definitions:
 {{range $message := $interface.Messages -}}
 // Message: {{$message.Name}}
 
 struct {{$message.RequestStruct.Name}};
 {{template "GenerateStructDefinitions" $message.RequestStruct}}
 {{if ne $message.ResponseStruct.Name "" -}}
 struct {{$message.ResponseStruct.Name}};
 {{template "GenerateStructDefinitions" $message.ResponseStruct}}
 {{end}}
 
 {{end}}
 {{end}}
 `