Revert vendor directory to support old golang (GOPATH mode)

gomodule is still in progress to migrate for now, hence multus
team decide to keep vendor directory to support build without
gomodule.

vendor/github.com/json-iterator/go/iter_skip.go

@@ -0,0 +1,129 @@
+package jsoniter
+
+import "fmt"
+
+// ReadNil reads a json object as nil and
+// returns whether it's a nil or not
+func (iter *Iterator) ReadNil() (ret bool) {
+	c := iter.nextToken()
+	if c == 'n' {
+		iter.skipThreeBytes('u', 'l', 'l') // null
+		return true
+	}
+	iter.unreadByte()
+	return false
+}
+
+// ReadBool reads a json object as BoolValue
+func (iter *Iterator) ReadBool() (ret bool) {
+	c := iter.nextToken()
+	if c == 't' {
+		iter.skipThreeBytes('r', 'u', 'e')
+		return true
+	}
+	if c == 'f' {
+		iter.skipFourBytes('a', 'l', 's', 'e')
+		return false
+	}
+	iter.ReportError("ReadBool", "expect t or f, but found "+string([]byte{c}))
+	return
+}
+
+// SkipAndReturnBytes skip next JSON element, and return its content as []byte.
+// The []byte can be kept, it is a copy of data.
+func (iter *Iterator) SkipAndReturnBytes() []byte {
+	iter.startCapture(iter.head)
+	iter.Skip()
+	return iter.stopCapture()
+}
+
+type captureBuffer struct {
+	startedAt int
+	captured  []byte
+}
+
+func (iter *Iterator) startCapture(captureStartedAt int) {
+	if iter.captured != nil {
+		panic("already in capture mode")
+	}
+	iter.captureStartedAt = captureStartedAt
+	iter.captured = make([]byte, 0, 32)
+}
+
+func (iter *Iterator) stopCapture() []byte {
+	if iter.captured == nil {
+		panic("not in capture mode")
+	}
+	captured := iter.captured
+	remaining := iter.buf[iter.captureStartedAt:iter.head]
+	iter.captureStartedAt = -1
+	iter.captured = nil
+	if len(captured) == 0 {
+		copied := make([]byte, len(remaining))
+		copy(copied, remaining)
+		return copied
+	}
+	captured = append(captured, remaining...)
+	return captured
+}
+
+// Skip skips a json object and positions to relatively the next json object
+func (iter *Iterator) Skip() {
+	c := iter.nextToken()
+	switch c {
+	case '"':
+		iter.skipString()
+	case 'n':
+		iter.skipThreeBytes('u', 'l', 'l') // null
+	case 't':
+		iter.skipThreeBytes('r', 'u', 'e') // true
+	case 'f':
+		iter.skipFourBytes('a', 'l', 's', 'e') // false
+	case '0':
+		iter.unreadByte()
+		iter.ReadFloat32()
+	case '-', '1', '2', '3', '4', '5', '6', '7', '8', '9':
+		iter.skipNumber()
+	case '[':
+		iter.skipArray()
+	case '{':
+		iter.skipObject()
+	default:
+		iter.ReportError("Skip", fmt.Sprintf("do not know how to skip: %v", c))
+		return
+	}
+}
+
+func (iter *Iterator) skipFourBytes(b1, b2, b3, b4 byte) {
+	if iter.readByte() != b1 {
+		iter.ReportError("skipFourBytes", fmt.Sprintf("expect %s", string([]byte{b1, b2, b3, b4})))
+		return
+	}
+	if iter.readByte() != b2 {
+		iter.ReportError("skipFourBytes", fmt.Sprintf("expect %s", string([]byte{b1, b2, b3, b4})))
+		return
+	}
+	if iter.readByte() != b3 {
+		iter.ReportError("skipFourBytes", fmt.Sprintf("expect %s", string([]byte{b1, b2, b3, b4})))
+		return
+	}
+	if iter.readByte() != b4 {
+		iter.ReportError("skipFourBytes", fmt.Sprintf("expect %s", string([]byte{b1, b2, b3, b4})))
+		return
+	}
+}
+
+func (iter *Iterator) skipThreeBytes(b1, b2, b3 byte) {
+	if iter.readByte() != b1 {
+		iter.ReportError("skipThreeBytes", fmt.Sprintf("expect %s", string([]byte{b1, b2, b3})))
+		return
+	}
+	if iter.readByte() != b2 {
+		iter.ReportError("skipThreeBytes", fmt.Sprintf("expect %s", string([]byte{b1, b2, b3})))
+		return
+	}
+	if iter.readByte() != b3 {
+		iter.ReportError("skipThreeBytes", fmt.Sprintf("expect %s", string([]byte{b1, b2, b3})))
+		return
+	}
+}