another false --> NULL return fix
another false --> NULL return fix

false --> NULL for failure return

BUG=

Review URL: https://codereview.appspot.com/7100052

git-svn-id: e8541e15acce502a64c929015570ad1648e548cd@7167 2bbb7eff-a529-9590-31e7-b0007b416f81

Cue/skia,Cue/skia,Cue/skia,Cue/skia