accounts/abi: add internalType information and fix issues (#20179)

* accounts/abi: fix various issues

The fixed issues include:

(1) If there is no return in a call function, unpack should
return nil error

(2) For some functions which have struct array as parameter,
it will also be detected and generate the struct definition

(3) For event, if it has non-indexed parameter, the parameter
name will also be assigned if empty. Also the internal struct
will be detected and generate struct defition if not exist.

(4) Fix annotation generation in event function

* accounts/abi: add new abi field internalType

* accounts: address comments and add tests

* accounts/abi: replace strings.ReplaceAll with strings.Replace

accounts/abi/bind/template.go

@@ -65,7 +65,7 @@ type tmplField struct {
 // tmplStruct is a wrapper around an abi.tuple contains a auto-generated
 // struct name.
 type tmplStruct struct {
-	Name   string       // Auto-generated struct name(We can't obtain the raw struct name through abi)
+	Name   string       // Auto-generated struct name(before solidity v0.5.11) or raw name.
 	Fields []*tmplField // Struct fields definition depends on the binding language.
 }
 
@@ -483,7 +483,7 @@ var (
 
 		// Parse{{.Normalized.Name}} is a log parse operation binding the contract event 0x{{printf "%x" .Original.ID}}.
 		//
-		// Solidity: {{.Original.String}}
+		// Solidity: {{formatevent .Original $structs}}
 		func (_{{$contract.Type}} *{{$contract.Type}}Filterer) Parse{{.Normalized.Name}}(log types.Log) (*{{$contract.Type}}{{.Normalized.Name}}, error) {
 			event := new({{$contract.Type}}{{.Normalized.Name}})
 			if err := _{{$contract.Type}}.contract.UnpackLog(event, "{{.Original.Name}}", log); err != nil {