Debugger: Introduce an option to force QT_LOGGING_TO_CONSOLE=1

Debug output is ephemeral in nature, and does not belong into system logs.
It happens, however, on Arch. Let people override this.

Fixes: QTCREATORBUG-25421
Change-Id: I5686e256d76e5a127e3269c5f407daf39bad683f
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/debugger/commonoptionspage.cpp

@@ -72,6 +72,7 @@ public:
             s.switchModeOnExit,
             s.showQmlObjectTree,
             s.stationaryEditorWhileStepping,
+            s.forceLoggingToConsole,
             s.registerForPostMortem,
             Stretch()
         };

src/plugins/debugger/debuggeractions.cpp

@@ -118,6 +118,12 @@ DebuggerSettings::DebuggerSettings()
                                                  "instead of keeping the next statement centered at "
                                                  "all times."));
 
+    forceLoggingToConsole.setSettingsKey(debugModeGroup, "ForceLoggingToConsole");
+    forceLoggingToConsole.setLabelText(tr("Force logging to console"));
+    forceLoggingToConsole.setToolTip(tr("This sets QT_LOGGING_TO_CONSOLE=1 in the environment "
+        "of the debugged program, preventing storing debug output "
+        "in system logs."));
+
     fontSizeFollowsEditor.setSettingsKey(debugModeGroup, "FontSizeFollowsEditor");
     fontSizeFollowsEditor.setToolTip(tr("Changes the font size in the debugger views when"
                                         "the font size in the main editor changes."));
@@ -563,6 +569,7 @@ DebuggerSettings::DebuggerSettings()
     page1.registerAspect(&switchModeOnExit);
     page1.registerAspect(&showQmlObjectTree);
     page1.registerAspect(&stationaryEditorWhileStepping);
+    page1.registerAspect(&forceLoggingToConsole);
 
     page1.registerAspect(&sourcePathMap);
 

src/plugins/debugger/debuggeractions.h

@@ -98,6 +98,7 @@ public:
     Utils::BoolAspect switchModeOnExit;
     Utils::BoolAspect showQmlObjectTree;
     Utils::BoolAspect stationaryEditorWhileStepping;
+    Utils::BoolAspect forceLoggingToConsole;
 
     SourcePathMapAspect sourcePathMap;
 

src/plugins/debugger/debuggerruncontrol.cpp

@@ -913,6 +913,9 @@ bool DebuggerRunTool::fixupParameters()
     if (rp.isNativeMixedDebugging())
         rp.inferior.environment.set("QV4_FORCE_INTERPRETER", "1");
 
+    if (debuggerSettings()->forceLoggingToConsole.value())
+        rp.inferior.environment.set("QT_LOGGING_TO_CONSOLE", "1");
+
     return true;
 }