Bug 564770 - provide graphics system parameter for child processes. r=dougt

toolkit/xre/nsAppRunner.cpp

@@ -3114,6 +3114,10 @@ XRE_main(int argc, char* argv[], const nsXREAppData* aAppData)
 #endif
 
 #if defined(MOZ_WIDGET_QT)
+    const char* qgraphicssystemARG = NULL;
+    ar = CheckArg("graphicssystem", PR_TRUE, &qgraphicssystemARG);
+    if (ar == ARG_FOUND)
+      PR_SetEnv(PR_smprintf("MOZ_QT_GRAPHICSSYSTEM=%s", qgraphicssystemARG));
     QApplication app(gArgc, gArgv);
 #endif
 #if defined(MOZ_WIDGET_GTK2)

toolkit/xre/nsQAppInstance.cpp

@@ -38,6 +38,7 @@
 
 #include "nsQAppInstance.h"
 #include <QApplication>
+#include "prenv.h"
 
 // declared in nsAppRunner.cpp
 extern int    gArgc;
@@ -53,8 +54,12 @@ nsQAppInstance::nsQAppInstance(int gArgc, char** gArgv)
 
 void nsQAppInstance::AddRef(void) {
   if (qApp) return;
-  if (!sQAppInstance)
+  if (!sQAppInstance) {
+    const char *graphicsSystem = PR_GetEnv("MOZ_QT_GRAPHICSSYSTEM");
+    if (graphicsSystem)
+      QApplication::setGraphicsSystem(QString(graphicsSystem));
     sQAppInstance = new nsQAppInstance(gArgc, gArgv);
+  }
   sQAppRefCount++;
 }