Clang: Show info bar for parse errors in header files

...because those errors can lead to a substantial performance/functional
regression.

The actual diagnostics (possibly with children) are shown as details in
the info bar.

The info bar can be hidden with the "Do Not Show Again" button.
Re-enabling the info bar is possible with the new editor tool bar
button.

Change-Id: I03394ff8e3c84127946b0b791930b28a385f5a46
Reviewed-by: David Schulz <david.schulz@qt.io>

src/libs/clangbackendipc/documentannotationschangedmessage.cpp

@@ -37,6 +37,7 @@ QDebug operator<<(QDebug debug, const DocumentAnnotationsChangedMessage &message
     debug.nospace() << "DocumentAnnotationsChangedMessage("
                     << message.fileContainer()
                     << ", " << message.diagnostics().size()
+                    << ", " << !message.firstHeaderErrorDiagnostic().text().isEmpty()
                     << ", " << message.highlightingMarks().size()
                     << ", " << message.skippedPreprocessorRanges().size()
                     << ")";
@@ -49,6 +50,7 @@ void PrintTo(const DocumentAnnotationsChangedMessage &message, ::std::ostream* o
     *os << "DocumentAnnotationsChangedMessage(";
     PrintTo(message.fileContainer(), os);
     *os << "," << message.diagnostics().size();
+    *os << "," << !message.firstHeaderErrorDiagnostic().text().isEmpty();
     *os << "," << message.highlightingMarks().size();
     *os << "," << message.skippedPreprocessorRanges().size();
     *os << ")";

src/libs/clangbackendipc/documentannotationschangedmessage.h

@@ -41,10 +41,12 @@ public:
     DocumentAnnotationsChangedMessage() = default;
     DocumentAnnotationsChangedMessage(const FileContainer &fileContainer,
                                       const QVector<DiagnosticContainer> &diagnostics,
+                                      const DiagnosticContainer &firstHeaderErrorDiagnostic_,
                                       const QVector<HighlightingMarkContainer> &highlightingMarks,
                                       const QVector<SourceRangeContainer> &skippedPreprocessorRanges)
         : fileContainer_(fileContainer),
           diagnostics_(diagnostics),
+          firstHeaderErrorDiagnostic_(firstHeaderErrorDiagnostic_),
           highlightingMarks_(highlightingMarks),
           skippedPreprocessorRanges_(skippedPreprocessorRanges)
     {
@@ -60,6 +62,11 @@ public:
         return diagnostics_;
     }
 
+    const DiagnosticContainer &firstHeaderErrorDiagnostic() const
+    {
+        return firstHeaderErrorDiagnostic_;
+    }
+
     const QVector<HighlightingMarkContainer> &highlightingMarks() const
     {
         return highlightingMarks_;
@@ -74,6 +81,7 @@ public:
     {
         out << message.fileContainer_;
         out << message.diagnostics_;
+        out << message.firstHeaderErrorDiagnostic_;
         out << message.highlightingMarks_;
         out << message.skippedPreprocessorRanges_;
 
@@ -84,6 +92,7 @@ public:
     {
         in >> message.fileContainer_;
         in >> message.diagnostics_;
+        in >> message.firstHeaderErrorDiagnostic_;
         in >> message.highlightingMarks_;
         in >> message.skippedPreprocessorRanges_;
 
@@ -95,6 +104,7 @@ public:
     {
         return first.fileContainer_ == second.fileContainer_
             && first.diagnostics_ == second.diagnostics_
+            && first.firstHeaderErrorDiagnostic_ == second.firstHeaderErrorDiagnostic_
             && first.highlightingMarks_ == second.highlightingMarks_
             && first.skippedPreprocessorRanges_ == second.skippedPreprocessorRanges_;
     }
@@ -102,6 +112,7 @@ public:
 private:
     FileContainer fileContainer_;
     QVector<DiagnosticContainer> diagnostics_;
+    DiagnosticContainer firstHeaderErrorDiagnostic_;
     QVector<HighlightingMarkContainer> highlightingMarks_;
     QVector<SourceRangeContainer> skippedPreprocessorRanges_;
 };