Clang: Provide tooltips

This includes also the query data for the help system (F1) for an
identifier under cursor.

Regressions (libclang changes necessary):
 - Function signatures do not contain default values.
 - Aliases are not resolved for/at:
   - template types
   - qualified name of a type

Fixes/Improvements:
 - Resolve "auto"
 - On a template type, show also the template parameter.
 - For a typedef like
     typedef long long superlong;
   the tooltip was "long long superlong", which was confusing.
   Now, "long long" is shown.

New:
 - Show first or \brief paragraph of a documentation comment.
 - Show size of a class at definition.
 - Show size of a field member in class definition.

Task-number: QTCREATORBUG-11259
Change-Id: Ie1a07930d0e882015d07dc43e35bb81a685cdeb8
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/plugins/clangcodemodel/clangmodelmanagersupport.cpp

@@ -29,11 +29,11 @@
 #include "clangeditordocumentprocessor.h"
 #include "clangutils.h"
 #include "clangfollowsymbol.h"
+#include "clanghoverhandler.h"
 #include "clangrefactoringengine.h"
 
 #include <coreplugin/editormanager/editormanager.h>
 #include <cpptools/cppfollowsymbolundercursor.h>
-#include <cpptools/cpphoverhandler.h>
 #include <cpptools/cppmodelmanager.h>
 #include <cpptools/editordocumenthandle.h>
 #include <cpptools/projectinfo.h>
@@ -114,7 +114,7 @@ CppTools::CppCompletionAssistProvider *ModelManagerSupportClang::completionAssis
 
 TextEditor::BaseHoverHandler *ModelManagerSupportClang::createHoverHandler()
 {
-    return new CppTools::CppHoverHandler;
+    return new Internal::ClangHoverHandler;
 }
 
 CppTools::FollowSymbolInterface &ModelManagerSupportClang::followSymbolInterface()