TaskTree: Unify TaskInterface::done(DoneResult) signal

Change the argument of TaskInterface::done() signal
from bool into DoneResult. Make it consistent with
other TaskTree API.

Introduce toDoneResult(bool success) helper.

Change-Id: I7b3041d7c1ed0317c76adbc1fd37448231e85f82
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: hjk <hjk@qt.io>

src/plugins/cmakeprojectmanager/cmakebuildstep.cpp

@@ -68,10 +68,12 @@ public:
     void start() final {
         Target *target = *task();
         if (!target) {
-            emit done(false);
+            emit done(DoneResult::Error);
             return;
         }
-        connect(target, &Target::parsingFinished, this, &TaskInterface::done);
+        connect(target, &Target::parsingFinished, this, [this](bool success) {
+            emit done(toDoneResult(success));
+        });
     }
 };