Fix missing copy in QgsSQLStatement copy constructor

No real bug here -- the value is unused outside of the constructor

src/core/qgssqlstatement.cpp

@@ -141,9 +141,10 @@ QgsSQLStatement::QgsSQLStatement( const QString &expr, bool allowFragments )
 }
 
 QgsSQLStatement::QgsSQLStatement( const QgsSQLStatement &other )
+  : mAllowFragments( other.mAllowFragments )
+  , mStatement( other.mStatement )
 {
-  mRootNode = ::parse( other.mStatement, mParserErrorString, other.mAllowFragments );
-  mStatement = other.mStatement;
+  mRootNode = ::parse( mStatement, mParserErrorString, mAllowFragments );
 }
 
 QgsSQLStatement &QgsSQLStatement::operator=( const QgsSQLStatement &other )