QText{En,De}coder: use DefaultConversion

In Qt 5, the flag to write the BOM was a negative: if IgnoreHeader
wasn't set, we would write it. That was the default in Qt 5 because
DefaultConversion was 0. But now it's a positive flag, DefaultConversion
was updated to set it, but we forgot to use it in the constructors of
these two classes.

[ChangeLog][Qt5CoreCompat][QTextEncoder] Fixed a bug that caused
QTextEncoder not to write the Byte Order Mark for UTF codecs when the
constructor without explicit flags was used.

Fixes: QTBUG-122795
Pick-to: 6.5 6.7
Change-Id: If1bf59ecbe014b569ba1fffd17c459af4e0e00c9
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/core5/codecs/qtextcodec.h b/src/core5/codecs/qtextcodec.h
index 0c239e1..b21393f 100644
--- a/src/core5/codecs/qtextcodec.h
+++ b/src/core5/codecs/qtextcodec.h
@@ -93,7 +93,8 @@ class Q_CORE5COMPAT_EXPORT QTextEncoder
 {
     Q_DISABLE_COPY(QTextEncoder)
 public:
-    explicit QTextEncoder(const QTextCodec *codec) : c(codec), state() {}
+    explicit QTextEncoder(const QTextCodec *codec)
+        : c(codec), state(QTextCodec::DefaultConversion) {}
     explicit QTextEncoder(const QTextCodec *codec, QTextCodec::ConversionFlags flags);
     ~QTextEncoder();
     QByteArray fromUnicode(const QString& str);
@@ -109,7 +110,8 @@ class Q_CORE5COMPAT_EXPORT QTextDecoder
 {
     Q_DISABLE_COPY(QTextDecoder)
 public:
-    explicit QTextDecoder(const QTextCodec *codec) : c(codec), state() {}
+    explicit QTextDecoder(const QTextCodec *codec)
+        : c(codec), state(QTextCodec::DefaultConversion) {}
     explicit QTextDecoder(const QTextCodec *codec, QTextCodec::ConversionFlags flags);
     ~QTextDecoder();
     QString toUnicode(const char* chars, int len);