Revert "Revert "Merge remote-tracking branch 'origin/4.15'""

This reverts commit f0a86d4510.

Reverting a merge doesn't "undo" it - the changes would be lost
forever even with subsequent merges.
So we need to revert the revert to get the changes.

Change-Id: I65928f876f4dc886561bed17c4b2aa42b388c1e3
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/plugins/projectexplorer/project.cpp

@@ -49,6 +49,7 @@
 #include <coreplugin/icore.h>
 #include <coreplugin/iversioncontrol.h>
 #include <coreplugin/vcsmanager.h>
+#include <coreplugin/editormanager/documentmodel.h>
 
 #include <projectexplorer/buildmanager.h>
 #include <projectexplorer/kitmanager.h>
@@ -1073,6 +1074,23 @@ QStringList Project::availableQmlPreviewTranslations(QString *errorMessage)
     });
 }
 
+QList<Core::IDocument *> Project::modifiedDocuments() const
+{
+    QList<Core::IDocument *> modifiedProjectDocuments;
+
+    for (Core::IDocument *doc : Core::DocumentModel::openedDocuments()) {
+        if (doc->isModified() && isKnownFile(doc->filePath()))
+            modifiedProjectDocuments.append(doc);
+    }
+
+    return modifiedProjectDocuments;
+}
+
+bool Project::isModified() const
+{
+    return !modifiedDocuments().isEmpty();
+}
+
 #if defined(WITH_TESTS)
 
 } // namespace ProjectExplorer