Bug 583499. Disable OpenGL layers by default on 10.5. r,a=joe

We need to do this to get QuickDraw plugins working with minimal hassle.

widget/src/xpwidgets/nsBaseWidget.cpp

@@ -787,6 +787,15 @@ nsBaseWidget::GetShouldAccelerate()
   PRBool forceAcceleration = PR_FALSE;
 #if defined(XP_WIN) || defined(XP_MACOSX) || defined(ANDROID) || (MOZ_PLATFORM_MAEMO > 5)
   PRBool accelerateByDefault = PR_TRUE;
+#elif defined(XP_MACOSX)
+/* quickdraw plugins don't work with OpenGL so we need to avoid OpenGL when we want to support
+ * them. e.g. 10.5 */
+# if defined(NP_NO_QUICKDRAW)
+  PRBool accelerateByDefault = PR_TRUE;
+# else
+  PRBool accelerateByDefault = PR_FALSE;
+# endif
+
 #else
   PRBool accelerateByDefault = PR_FALSE;
 #endif