QStyleHelper: Use palette cache key in pixmap key

This reverts commit d7bcdc3a442b99c2caebd4cfd38de67e14090e05.

Now that QPalette::setBrush() is a bit smarter (see
c564779c071b35fddb76f4e50afda4305b634651), we can be
confident the palette's cache key won't change so often.
Therefore, we can use it again as part of every pixmap's
cache key.

Change-Id: I5cab2296a937f9149c7745291e0442eea24f4e9d
Task-number: QTBUG-65475
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 1 insertions, 20 deletions

diff --git a/src/widgets/styles/qstylehelper.cpp b/src/widgets/styles/qstylehelper.cpp
index 4f498efac0..373699a7aa 100644
--- a/src/widgets/styles/qstylehelper.cpp
+++ b/src/widgets/styles/qstylehelper.cpp
@@ -51,8 +51,6 @@
 
 #include "qstylehelper_p.h"
 #include <qstringbuilder.h>
-#include <qdatastream.h>
-#include <qcryptographichash.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -66,6 +64,7 @@ QString uniqueName(const QString &key, const QStyleOption *option, const QSize &
     QString tmp = key % HexString<uint>(option->state)
                       % HexString<uint>(option->direction)
                       % HexString<uint>(complexOption ? uint(complexOption->activeSubControls) : 0u)
+                      % HexString<quint64>(option->palette.cacheKey())
                       % HexString<uint>(size.width())
                       % HexString<uint>(size.height());
 
@@ -77,24 +76,6 @@ QString uniqueName(const QString &key, const QStyleOption *option, const QSize &
     }
 #endif // QT_CONFIG(spinbox)
 
-    // QTBUG-56743, try to create a palette cache key reflecting the value,
-    // as leaks may occur in conjunction with QStyleSheetStyle/QRenderRule modifying
-    // palettes when using QPalette::cacheKey()
-    if (option->palette != QGuiApplication::palette()) {
-        tmp.append(QLatin1Char('P'));
-#ifndef QT_NO_DATASTREAM
-        QByteArray key;
-        key.reserve(5120); // Observed 5040B for a serialized palette on 64bit
-        {
-            QDataStream str(&key, QIODevice::WriteOnly);
-            str << option->palette;
-        }
-        const QByteArray sha1 = QCryptographicHash::hash(key, QCryptographicHash::Sha1).toHex();
-        tmp.append(QString::fromLatin1(sha1));
-#else // QT_NO_DATASTREAM
-        tmp.append(QString::number(option->palette.cacheKey(), 16));
-#endif // !QT_NO_DATASTREAM
-    }
     return tmp;
 }