Bug 595194 - CGL context creation crashes on Mac Tryserver - r=bas.schouten a=blocking2.0

--HG--
extra : rebase_source : b8e2bfde25a0acb33258e77ebd36959c91f73af8

gfx/thebes/GLContextProviderCGL.mm

@@ -515,7 +515,7 @@ GLContextProviderCGL::GetGlobalContext()
         gGlobalContext = CreateOffscreenFBOContext(gfxIntSize(16, 16),
                                                    ContextFormat(ContextFormat::BasicRGB24),
                                                    PR_FALSE);
-        if (gGlobalContext && !static_cast<GLContextCGL*>(gGlobalContext.get())->Init()) {
+        if (!gGlobalContext || !static_cast<GLContextCGL*>(gGlobalContext.get())->Init()) {
             NS_WARNING("Couldn't init gGlobalContext.");
             gGlobalContext = nsnull;
             return nsnull;