Add workaround to enable last.fm debugging.

liblastfm checks QCoreApplication::arguments() for "--debug". That's not
easy to avoid, so add a synonym debug flag "--debug-last-fm" which has identical
functionality in Amarok, but doesn't trigger the non-functional last.fm debug
mode.

This is not pretty, but it is pretty contained and makes reasonable last.fm
bughunting possible. Should lastfm/liblastfm#37 ever
get merged, this commit can be reverted, but that might not happen anytime soon
as the PR has been pending for 4 years and latest liblastfm release was almost
10 years ago.

BUG: 485415

Author: Mazhoon

src/App.cpp

@@ -371,6 +371,8 @@ App::initCliArgs(QCommandLineParser *parser)
     options.append(QCommandLineOption("queue", i18n("Queue URLs after the currently playing track")));
     options.append(QCommandLineOption(QStringList() << "l" << "load", i18n("Load URLs, replacing current playlist")));
     options.append(QCommandLineOption(QStringList() << "d" << "debug", i18n("Print verbose debugging information")));
+    // HACK should https://github.com/lastfm/liblastfm/pull/37 ever get merged, this option can be removed
+    options.append(QCommandLineOption("debug-with-lastfm", i18n("Print verbose debugging information")));
     options.append(QCommandLineOption("debug-audio", i18n("Print verbose debugging information from the audio system")));
     options.append(QCommandLineOption(QStringList() << "c" << "coloroff", i18n("Disable colorization for debug output.")));
     options.append(QCommandLineOption(QStringList() << "m" << "multipleinstances", i18n("Allow running multiple Amarok instances")));

src/main.cpp

@@ -347,7 +347,7 @@ int main( int argc, char *argv[] )
                      &app, &App::activateRequested);
 
     const bool debugColorsEnabled = !parser.isSet( "coloroff" );
-    const bool debugEnabled = parser.isSet( "debug" );
+    const bool debugEnabled = parser.isSet( "debug" ) || parser.isSet( "debug-with-lastfm" ); // HACK see App::initCliArgs
 
     Debug::setDebugEnabled( debugEnabled );
     Debug::setColoredDebug( debugColorsEnabled );