TileGrid: earliest need not be a pointer anymore
TileGrid: earliest need not be a pointer anymore

BUG=skia:

Review URL: https://codereview.chromium.org/625573003

jtg-gg/skia,UBERMALLOW/external_skia,tmpvar/skia.cc,pcwalton/skia,invisiblek/android_external_skia,BrokenROM/external_skia,nvoron23/skia,TeamTwisted/external_skia,ominux/skia,noselhq/skia,nfxosp/platform_external_skia,AOSPB/external_skia,UBERMALLOW/external_skia,geekboxzone/mmallow_external_skia,BrokenROM/external_skia,Infinitive-OS/platform_external_skia,HalCanary/skia-hc,pcwalton/skia,rubenvb/skia,samuelig/skia,Infinitive-OS/platform_external_skia,rubenvb/skia,scroggo/skia,Jichao/skia,spezi77/android_external_skia,shahrzadmn/skia,VRToxin-AOSP/android_external_skia,VRToxin-AOSP/android_external_skia,MarshedOut/android_external_skia,MarshedOut/android_external_skia,nvoron23/skia,OneRom/external_skia,w3nd1go/android_external_skia,google/skia,jtg-gg/skia,MonkeyZZZZ/platform_external_skia,geekboxzone/mmallow_external_skia,Jichao/skia,samuelig/skia,HalCanary/skia-hc,Infinitive-OS/platform_external_skia,noselhq/skia,vanish87/skia,MonkeyZZZZ/platform_external_skia,todotodoo/skia,nfxosp/platform_external_skia,tmpvar/skia.cc,Igalia/skia,Infinitive-OS/platform_external_skia,rubenvb/skia,MinimalOS-AOSP/platform_external_skia,rubenvb/skia,TeamTwisted/external_skia,VRToxin-AOSP/android_external_skia,rubenvb/skia,shahrzadmn/skia,qrealka/skia-hc,OneRom/external_skia,aosp-mirror/platform_external_skia,AOSP-YU/platform_external_skia,noselhq/skia,google/skia,Jichao/skia,noselhq/skia,tmpvar/skia.cc,TeamExodus/external_skia,HalCanary/skia-hc,shahrzadmn/skia,nfxosp/platform_external_skia,DiamondLovesYou/skia-sys,PAC-ROM/android_external_skia,MarshedOut/android_external_skia,PAC-ROM/android_external_skia,UBERMALLOW/external_skia,Jichao/skia,DiamondLovesYou/skia-sys,MonkeyZZZZ/platform_external_skia,BrokenROM/external_skia,PAC-ROM/android_external_skia,vanish87/skia,YUPlayGodDev/platform_external_skia,UBERMALLOW/external_skia,w3nd1go/android_external_skia,boulzordev/android_external_skia,nvoron23/skia,samuelig/skia,tmpvar/skia.cc,spezi77/android_external_skia,ominux/skia,nfxosp/platform_external_skia,shahrzadmn/skia,nfxosp/platform_external_skia,aosp-mirror/platform_external_skia,AOSP-YU/platform_external_skia,scroggo/skia,TeamTwisted/external_skia,YUPlayGodDev/platform_external_skia,boulzordev/android_external_skia,samuelig/skia,amyvmiwei/skia,MarshedOut/android_external_skia,YUPlayGodDev/platform_external_skia,rubenvb/skia,invisiblek/android_external_skia,BrokenROM/external_skia,Igalia/skia,aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,qrealka/skia-hc,Igalia/skia,boulzordev/android_external_skia,google/skia,TeamExodus/external_skia,MonkeyZZZZ/platform_external_skia,UBERMALLOW/external_skia,boulzordev/android_external_skia,todotodoo/skia,todotodoo/skia,HalCanary/skia-hc,Igalia/skia,pcwalton/skia,amyvmiwei/skia,MinimalOS-AOSP/platform_external_skia,HalCanary/skia-hc,PAC-ROM/android_external_skia,geekboxzone/mmallow_external_skia,invisiblek/android_external_skia,Jichao/skia,AOSP-YU/platform_external_skia,pcwalton/skia,pcwalton/skia,AOSP-YU/platform_external_skia,samuelig/skia,BrokenROM/external_skia,MarshedOut/android_external_skia,OneRom/external_skia,invisiblek/android_external_skia,timduru/platform-external-skia,boulzordev/android_external_skia,invisiblek/android_external_skia,pcwalton/skia,AOSP-YU/platform_external_skia,Hikari-no-Tenshi/android_external_skia,BrokenROM/external_skia,boulzordev/android_external_skia,TeamTwisted/external_skia,chenlian2015/skia_from_google,MonkeyZZZZ/platform_external_skia,VRToxin-AOSP/android_external_skia,shahrzadmn/skia,MinimalOS-AOSP/platform_external_skia,vanish87/skia,rubenvb/skia,MarshedOut/android_external_skia,spezi77/android_external_skia,tmpvar/skia.cc,TeamTwisted/external_skia,tmpvar/skia.cc,Infinitive-OS/platform_external_skia,boulzordev/android_external_skia,DiamondLovesYou/skia-sys,UBERMALLOW/external_skia,TeamTwisted/external_skia,noselhq/skia,BrokenROM/external_skia,Hikari-no-Tenshi/android_external_skia,samuelig/skia,w3nd1go/android_external_skia,MinimalOS-AOSP/platform_external_skia,geekboxzone/mmallow_external_skia,HalCanary/skia-hc,UBERMALLOW/external_skia,OneRom/external_skia,Igalia/skia,todotodoo/skia,google/skia,HalCanary/skia-hc,Infinitive-OS/platform_external_skia,OneRom/external_skia,rubenvb/skia,TeamExodus/external_skia,w3nd1go/android_external_skia,google/skia,ominux/skia,Jichao/skia,amyvmiwei/skia,Jichao/skia,Hikari-no-Tenshi/android_external_skia,ominux/skia,MinimalOS-AOSP/platform_external_skia,jtg-gg/skia,qrealka/skia-hc,jtg-gg/skia,nvoron23/skia,nvoron23/skia,vanish87/skia,rubenvb/skia,w3nd1go/android_external_skia,AOSPB/external_skia,nfxosp/platform_external_skia,HalCanary/skia-hc,HalCanary/skia-hc,nvoron23/skia,YUPlayGodDev/platform_external_skia,shahrzadmn/skia,scroggo/skia,AOSPB/external_skia,google/skia,jtg-gg/skia,nvoron23/skia,scroggo/skia,invisiblek/android_external_skia,aosp-mirror/platform_external_skia,vanish87/skia,scroggo/skia,OneRom/external_skia,YUPlayGodDev/platform_external_skia,invisiblek/android_external_skia,geekboxzone/mmallow_external_skia,timduru/platform-external-skia,todotodoo/skia,MarshedOut/android_external_skia,nvoron23/skia,chenlian2015/skia_from_google,google/skia,tmpvar/skia.cc,TeamExodus/external_skia,ominux/skia,nfxosp/platform_external_skia,OneRom/external_skia,MonkeyZZZZ/platform_external_skia,chenlian2015/skia_from_google,Infinitive-OS/platform_external_skia,AOSP-YU/platform_external_skia,MinimalOS-AOSP/platform_external_skia,google/skia,geekboxzone/mmallow_external_skia,geekboxzone/mmallow_external_skia,YUPlayGodDev/platform_external_skia,YUPlayGodDev/platform_external_skia,Hikari-no-Tenshi/android_external_skia,qrealka/skia-hc,spezi77/android_external_skia,vanish87/skia,MinimalOS-AOSP/platform_external_skia,spezi77/android_external_skia,MarshedOut/android_external_skia,aosp-mirror/platform_external_skia,YUPlayGodDev/platform_external_skia,VRToxin-AOSP/android_external_skia,google/skia,TeamTwisted/external_skia,vanish87/skia,Hikari-no-Tenshi/android_external_skia,MarshedOut/android_external_skia,AOSP-YU/platform_external_skia,jtg-gg/skia,w3nd1go/android_external_skia,MonkeyZZZZ/platform_external_skia,boulzordev/android_external_skia,timduru/platform-external-skia,qrealka/skia-hc,aosp-mirror/platform_external_skia,BrokenROM/external_skia,VRToxin-AOSP/android_external_skia,TeamExodus/external_skia,geekboxzone/mmallow_external_skia,AOSP-YU/platform_external_skia,pcwalton/skia,pcwalton/skia,noselhq/skia,DiamondLovesYou/skia-sys,tmpvar/skia.cc,AOSPB/external_skia,vanish87/skia,jtg-gg/skia,TeamExodus/external_skia,UBERMALLOW/external_skia,scroggo/skia,YUPlayGodDev/platform_external_skia,scroggo/skia,PAC-ROM/android_external_skia,todotodoo/skia,geekboxzone/mmallow_external_skia,AOSPB/external_skia,ominux/skia,w3nd1go/android_external_skia,tmpvar/skia.cc,scroggo/skia,TeamExodus/external_skia,PAC-ROM/android_external_skia,OneRom/external_skia,TeamTwisted/external_skia,PAC-ROM/android_external_skia,aosp-mirror/platform_external_skia,timduru/platform-external-skia,samuelig/skia,DiamondLovesYou/skia-sys,invisiblek/android_external_skia,MonkeyZZZZ/platform_external_skia,timduru/platform-external-skia,qrealka/skia-hc,Igalia/skia,TeamTwisted/external_skia,PAC-ROM/android_external_skia,chenlian2015/skia_from_google,AOSPB/external_skia,VRToxin-AOSP/android_external_skia,DiamondLovesYou/skia-sys,noselhq/skia,Infinitive-OS/platform_external_skia,VRToxin-AOSP/android_external_skia,AOSPB/external_skia,AOSPB/external_skia,noselhq/skia,boulzordev/android_external_skia,timduru/platform-external-skia,qrealka/skia-hc,nvoron23/skia,PAC-ROM/android_external_skia,Jichao/skia,Hikari-no-Tenshi/android_external_skia,ominux/skia,TeamExodus/external_skia,samuelig/skia,qrealka/skia-hc,w3nd1go/android_external_skia,Igalia/skia,vanish87/skia,chenlian2015/skia_from_google,rubenvb/skia,shahrzadmn/skia,pcwalton/skia,chenlian2015/skia_from_google,amyvmiwei/skia,Infinitive-OS/platform_external_skia,todotodoo/skia,MinimalOS-AOSP/platform_external_skia,ominux/skia,shahrzadmn/skia,nfxosp/platform_external_skia,google/skia,shahrzadmn/skia,Hikari-no-Tenshi/android_external_skia,chenlian2015/skia_from_google,ominux/skia,MinimalOS-AOSP/platform_external_skia,nfxosp/platform_external_skia,Igalia/skia,aosp-mirror/platform_external_skia,timduru/platform-external-skia,OneRom/external_skia,todotodoo/skia,w3nd1go/android_external_skia,DiamondLovesYou/skia-sys,AOSP-YU/platform_external_skia,UBERMALLOW/external_skia,MonkeyZZZZ/platform_external_skia,spezi77/android_external_skia,TeamExodus/external_skia,amyvmiwei/skia,aosp-mirror/platform_external_skia,noselhq/skia,amyvmiwei/skia,VRToxin-AOSP/android_external_skia,amyvmiwei/skia,Jichao/skia,amyvmiwei/skia,AOSPB/external_skia,todotodoo/skia