PVS-Studio warning V517 for QT

void Node::setPageType(const QString& t)
{
  if ((t == "API") || (t == "api"))
    pageType_ = ApiPage;
  else if (t == "howto")             <<<===
    pageType_ = HowToPage;
  else if (t == "overview")
    pageType_ = OverviewPage;
  else if (t == "tutorial")
    pageType_ = TutorialPage;
  else if (t == "howto")             <<<===
    pageType_ = HowToPage;
  else if (t == "article")
    pageType_ = ArticlePage;
  else if (t == "example")
    pageType_ = ExamplePage;
  else if (t == "ditamap")
    pageType_ = DitaMapPage;
}

This suspicious code was found in QT project by PVS-Studio static code analyzer.
Warning message is:
V517 The use of 'if (A) {...} else if (A) {...}' pattern was detected. There is a probability of logical error presence. Check lines: 386, 392. node.cpp 386

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