Designer: Update C++ code model on an object name change in designer

We try to locate the old symbol name in the generated ui header and
rename the symbol in the background.

Task-number: QTCREATORBUG-1179
Change-Id: Iaf68e3922cd728cbc87d0dc97125e34b8bdaa6be
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/qmakeprojectmanager/qmakeproject.cpp

@@ -532,6 +532,11 @@ void QmakeBuildSystem::scheduleUpdateAllNowOrLater()
         scheduleUpdateAll(QmakeProFile::ParseLater);
 }
 
+ExtraCompiler *QmakeBuildSystem::extraCompilerForSource(const Utils::FilePath &source)
+{
+    return m_rootProFile->extraCompilerForSource(source);
+}
+
 QmakeBuildConfiguration *QmakeBuildSystem::qmakeBuildConfiguration() const
 {
     return static_cast<QmakeBuildConfiguration *>(BuildSystem::buildConfiguration());