CMake: Trigger cmake run *before* build when files changed

Make sure to run cmake *before* cmake --build when cmake files just
got saved. This helps e.g. when editing CMakeLists.txt files and the
hitting "Built" and "Save all" (or "Always save before build").

Task-number: QTCREATORBUG-16187
Change-Id: I16b1d02eb342a447003380946ce7a9d785476a0e
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

src/plugins/cmakeprojectmanager/builddirmanager.h

@@ -44,6 +44,8 @@
 QT_FORWARD_DECLARE_CLASS(QTemporaryDir);
 QT_FORWARD_DECLARE_CLASS(QFileSystemWatcher);
 
+namespace Core { class IDocument; }
+
 namespace ProjectExplorer {
 class FileNode;
 class IOutputParser;
@@ -74,6 +76,7 @@ public:
     void forceReparse();
     void maybeForceReparse(); // Only reparse if the configuration has changed...
     void resetData();
+    bool updateCMakeStateBeforeBuild();
     bool persistCMakeState();
 
     void generateProjectTree(CMakeProjectNode *root);
@@ -83,6 +86,7 @@ public:
 
     void checkConfiguration();
 
+    void handleDocumentSaves(Core::IDocument *document);
     void handleCmakeFileChange();
 
 signals: