Move mimetype definitions to plugin specs

- Avoids the hassle of QRC files and manually registering mime types
- Avoids performance regressions because of mime types that are
  registered after mime database has been used
- Makes it technically possible to detect that a disabled plugin could
  handle a mime type if it was enabled

Change-Id: I373008b1b56e9c6b4853055f20b3eeb112a6eff9
Reviewed-by: Christian Stenger <christian.stenger@qt.io>
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/debuggerplugin.cpp

@@ -117,7 +117,6 @@
 #include <utils/checkablemessagebox.h>
 #include <utils/fancymainwindow.h>
 #include <utils/hostosinfo.h>
-#include <utils/mimetypes/mimedatabase.h>
 #include <utils/proxyaction.h>
 #include <utils/qtcassert.h>
 #include <utils/savedaction.h>
@@ -1275,8 +1274,6 @@ bool DebuggerPluginPrivate::initialize(const QStringList &arguments,
     QString *errorMessage)
 {
     Q_UNUSED(errorMessage);
-    Utils::MimeDatabase::addMimeTypes(QLatin1String(":/debugger/Debugger.mimetypes.xml"));
-
     m_arguments = arguments;
     if (!m_arguments.isEmpty())
         connect(ProjectExplorerPlugin::instance(), &ProjectExplorerPlugin::finishedInitialization,