Fix NULL access
Fix NULL access

BUG=skia:

TBR=egdaniel@google.com

Review URL: https://codereview.chromium.org/1157363004

HalCanary/skia-hc,vanish87/skia,pcwalton/skia,ominux/skia,ominux/skia,rubenvb/skia,Hikari-no-Tenshi/android_external_skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,google/skia,pcwalton/skia,tmpvar/skia.cc,rubenvb/skia,rubenvb/skia,google/skia,Jichao/skia,shahrzadmn/skia,Jichao/skia,qrealka/skia-hc,todotodoo/skia,qrealka/skia-hc,Hikari-no-Tenshi/android_external_skia,Hikari-no-Tenshi/android_external_skia,HalCanary/skia-hc,vanish87/skia,noselhq/skia,nvoron23/skia,nvoron23/skia,noselhq/skia,noselhq/skia,aosp-mirror/platform_external_skia,Jichao/skia,vanish87/skia,ominux/skia,qrealka/skia-hc,rubenvb/skia,noselhq/skia,Jichao/skia,nvoron23/skia,pcwalton/skia,aosp-mirror/platform_external_skia,todotodoo/skia,qrealka/skia-hc,ominux/skia,todotodoo/skia,Jichao/skia,noselhq/skia,todotodoo/skia,nvoron23/skia,google/skia,shahrzadmn/skia,tmpvar/skia.cc,Jichao/skia,tmpvar/skia.cc,Hikari-no-Tenshi/android_external_skia,pcwalton/skia,Jichao/skia,shahrzadmn/skia,ominux/skia,noselhq/skia,qrealka/skia-hc,noselhq/skia,tmpvar/skia.cc,vanish87/skia,qrealka/skia-hc,google/skia,HalCanary/skia-hc,HalCanary/skia-hc,vanish87/skia,pcwalton/skia,shahrzadmn/skia,todotodoo/skia,ominux/skia,rubenvb/skia,noselhq/skia,vanish87/skia,HalCanary/skia-hc,shahrzadmn/skia,tmpvar/skia.cc,nvoron23/skia,google/skia,aosp-mirror/platform_external_skia,nvoron23/skia,vanish87/skia,pcwalton/skia,Jichao/skia,aosp-mirror/platform_external_skia,ominux/skia,rubenvb/skia,Hikari-no-Tenshi/android_external_skia,HalCanary/skia-hc,pcwalton/skia,rubenvb/skia,rubenvb/skia,qrealka/skia-hc,tmpvar/skia.cc,shahrzadmn/skia,todotodoo/skia,todotodoo/skia,Hikari-no-Tenshi/android_external_skia,nvoron23/skia,google/skia,Jichao/skia,google/skia,aosp-mirror/platform_external_skia,nvoron23/skia,qrealka/skia-hc,tmpvar/skia.cc,Hikari-no-Tenshi/android_external_skia,shahrzadmn/skia,vanish87/skia,aosp-mirror/platform_external_skia,google/skia,rubenvb/skia,google/skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,tmpvar/skia.cc,Hikari-no-Tenshi/android_external_skia,todotodoo/skia,vanish87/skia,HalCanary/skia-hc,shahrzadmn/skia,ominux/skia,noselhq/skia,tmpvar/skia.cc,nvoron23/skia,ominux/skia,shahrzadmn/skia,google/skia,rubenvb/skia,HalCanary/skia-hc,todotodoo/skia,pcwalton/skia,pcwalton/skia,aosp-mirror/platform_external_skia