Apply constant binding removal optimization to QProperty bindings

This applies the logic from 7cb6dce1f3e140ea68d6b05281950f212fc99d38 to
non-QQmlAbstractBinding bindings, too.
The logic to detect whether a binding has no dependencies has consider
the QPropertyBindingPrivate's dependency  observer count.

In addition, change the existing detection logic to remove properties
without a context, too. The  original logic probably wanted to guard
against accessing binding->context()->unresolvedNames when context was
nullptr; however, the check should have tested "context ->
unresolvedNames", not "context and unresolvedNames". And after the
refactoring which introduced hasUnresolvedNames() as a function, the
context check became completely superfluous.

Fixes: QTBUG-92996
Change-Id: Ia3bc39e184f431210b3bb2d38154acf820525e98
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/qml/qml/qqmlpropertybinding_p.h b/src/qml/qml/qqmlpropertybinding_p.h
index 6220dce06a..83c58f8254 100644
--- a/src/qml/qml/qqmlpropertybinding_p.h
+++ b/src/qml/qml/qqmlpropertybinding_p.h
@@ -131,6 +131,8 @@ public:
         return reinterpret_cast<QQmlPropertyBinding *>(address)->evaluate(metaType, dataPtr);
     }
 
+    bool hasDependencies();
+
 private:
     bool evaluate(QMetaType metaType, void *dataPtr);