Add debug trap to track down crash.
Add debug trap to track down crash.

Original CL by arthurhsu: http://codereview.appspot.com/5144046/

BUG=CR 94421

Review URL: http://codereview.appspot.com/5132051

git-svn-id: e8541e15acce502a64c929015570ad1648e548cd@2344 2bbb7eff-a529-9590-31e7-b0007b416f81

Frankie-666/color-emoji.skia,hbwhlklive/color-emoji.skia,MatChung/color-emoji.skia,hbwhlklive/color-emoji.skia,Hankuo/color-emoji.skia,Frankie-666/color-emoji.skia,Hankuo/color-emoji.skia,MatChung/color-emoji.skia,MatChung/color-emoji.skia,Frankie-666/color-emoji.skia,Frankie-666/color-emoji.skia,Hankuo/color-emoji.skia,Hankuo/color-emoji.skia,MatChung/color-emoji.skia,hbwhlklive/color-emoji.skia,MatChung/color-emoji.skia,Hankuo/color-emoji.skia,hbwhlklive/color-emoji.skia,hbwhlklive/color-emoji.skia,Frankie-666/color-emoji.skia,Hankuo/color-emoji.skia,MatChung/color-emoji.skia,hbwhlklive/color-emoji.skia,Frankie-666/color-emoji.skia