Fix some typos (grpc-ecosystem#601)

runtime/marshal_jsonpb.go

@@ -50,7 +50,7 @@ func (j *JSONPb) marshalTo(w io.Writer, v interface{}) error {
 }
 
 // marshalNonProto marshals a non-message field of a protobuf message.
-// This function does not correctly marshals arbitary data structure into JSON,
+// This function does not correctly marshals arbitrary data structure into JSON,
 // but it is only capable of marshaling non-message field values of protobuf,
 // i.e. primitive types, enums; pointers to primitives or enums; maps from
 // integer/string types to primitives/enums/pointers to messages.

runtime/marshaler_registry.go

@@ -68,7 +68,7 @@ func (m marshalerRegistry) add(mime string, marshaler Marshaler) error {
 // It allows for a mapping of case-sensitive Content-Type MIME type string to runtime.Marshaler interfaces.
 //
 // For example, you could allow the client to specify the use of the runtime.JSONPb marshaler
-// with a "applicaton/jsonpb" Content-Type and the use of the runtime.JSONBuiltin marshaler
+// with a "application/jsonpb" Content-Type and the use of the runtime.JSONBuiltin marshaler
 // with a "application/json" Content-Type.
 // "*" can be used to match any Content-Type.
 // This can be attached to a ServerMux with the marshaler option.

utilities/pattern.go

@@ -17,6 +17,6 @@ const (
 	OpConcatN
 	// OpCapture pops an item and binds it to the variable
 	OpCapture
-	// OpEnd is the least postive invalid opcode.
+	// OpEnd is the least positive invalid opcode.
 	OpEnd
 )