Remove now-nonexistent SkCountdown.h from public_headers.
Remove now-nonexistent SkCountdown.h from public_headers.

Seems to be breaking Chrome's GN build.

R=rmistry@google.com
TBR=rmistry
BUG=skia:

Author: senorblanco@chromium.org

Review URL: https://codereview.chromium.org/359183002

TeamExodus/external_skia,ominux/skia,MarshedOut/android_external_skia,boulzordev/android_external_skia,MinimalOS/android_external_chromium_org_third_party_skia,MinimalOS-AOSP/platform_external_skia,rubenvb/skia,Infinitive-OS/platform_external_skia,ench0/external_chromium_org_third_party_skia,VRToxin-AOSP/android_external_skia,amyvmiwei/skia,MinimalOS/android_external_chromium_org_third_party_skia,ominux/skia,Jichao/skia,OptiPop/external_chromium_org_third_party_skia,TeamTwisted/external_skia,Jichao/skia,chenlian2015/skia_from_google,Fusion-Rom/external_chromium_org_third_party_skia,spezi77/android_external_skia,nvoron23/skia,qrealka/skia-hc,jtg-gg/skia,HalCanary/skia-hc,PAC-ROM/android_external_skia,DARKPOP/external_chromium_org_third_party_skia,DARKPOP/external_chromium_org_third_party_skia,android-ia/platform_external_chromium_org_third_party_skia,invisiblek/android_external_skia,MonkeyZZZZ/platform_external_skia,MinimalOS/external_chromium_org_third_party_skia,nfxosp/platform_external_skia,android-ia/platform_external_chromium_org_third_party_skia,google/skia,TeamEOS/external_chromium_org_third_party_skia,UBERMALLOW/external_skia,AOSPB/external_skia,aosp-mirror/platform_external_skia,PAC-ROM/android_external_skia,BrokenROM/external_skia,TeamEOS/external_chromium_org_third_party_skia,AOSPB/external_skia,tmpvar/skia.cc,nfxosp/platform_external_skia,geekboxzone/mmallow_external_skia,samuelig/skia,MinimalOS/external_chromium_org_third_party_skia,BrokenROM/external_skia,noselhq/skia,google/skia,nvoron23/skia,DARKPOP/external_chromium_org_third_party_skia,MarshedOut/android_external_skia,tmpvar/skia.cc,YUPlayGodDev/platform_external_skia,spezi77/android_external_skia,scroggo/skia,TeamExodus/external_skia,TeamEOS/external_chromium_org_third_party_skia,BrokenROM/external_skia,boulzordev/android_external_skia,AOSP-YU/platform_external_skia,boulzordev/android_external_skia,OneRom/external_skia,todotodoo/skia,tmpvar/skia.cc,ench0/external_chromium_org_third_party_skia,samuelig/skia,invisiblek/android_external_skia,samuelig/skia,MyAOSP/external_chromium_org_third_party_skia,OneRom/external_skia,UBERMALLOW/external_skia,invisiblek/android_external_skia,geekboxzone/mmallow_external_skia,mydongistiny/external_chromium_org_third_party_skia,rubenvb/skia,HalCanary/skia-hc,rubenvb/skia,FusionSP/external_chromium_org_third_party_skia,pcwalton/skia,FusionSP/external_chromium_org_third_party_skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,MinimalOS-AOSP/platform_external_skia,pcwalton/skia,shahrzadmn/skia,aosp-mirror/platform_external_skia,OptiPop/external_chromium_org_third_party_skia,invisiblek/android_external_skia,DARKPOP/external_chromium_org_third_party_skia,noselhq/skia,chenlian2015/skia_from_google,HalCanary/skia-hc,tmpvar/skia.cc,MinimalOS/external_chromium_org_third_party_skia,Jichao/skia,shahrzadmn/skia,geekboxzone/mmallow_external_skia,timduru/platform-external-skia,TeamExodus/external_skia,ominux/skia,Hikari-no-Tenshi/android_external_skia,vanish87/skia,mydongistiny/external_chromium_org_third_party_skia,Omegaphora/external_chromium_org_third_party_skia,shahrzadmn/skia,Igalia/skia,nvoron23/skia,ominux/skia,Jichao/skia,nfxosp/platform_external_skia,noselhq/skia,Infinitive-OS/platform_external_skia,jtg-gg/skia,Hikari-no-Tenshi/android_external_skia,todotodoo/skia,VRToxin-AOSP/android_external_skia,Jichao/skia,YUPlayGodDev/platform_external_skia,VRToxin-AOSP/android_external_skia,Igalia/skia,DARKPOP/external_chromium_org_third_party_skia,nvoron23/skia,w3nd1go/android_external_skia,Jichao/skia,Hikari-no-Tenshi/android_external_skia,geekboxzone/mmallow_external_skia,Omegaphora/external_chromium_org_third_party_skia,qrealka/skia-hc,AOSP-YU/platform_external_skia,boulzordev/android_external_skia,xin3liang/platform_external_chromium_org_third_party_skia,YUPlayGodDev/platform_external_skia,google/skia,BrokenROM/external_skia,w3nd1go/android_external_skia,TeamTwisted/external_skia,qrealka/skia-hc,FusionSP/external_chromium_org_third_party_skia,w3nd1go/android_external_skia,AOSP-YU/platform_external_skia,MyAOSP/external_chromium_org_third_party_skia,HalCanary/skia-hc,google/skia,chenlian2015/skia_from_google,ominux/skia,OneRom/external_skia,timduru/platform-external-skia,todotodoo/skia,invisiblek/android_external_skia,google/skia,VRToxin-AOSP/android_external_skia,xin3liang/platform_external_chromium_org_third_party_skia,geekboxzone/mmallow_external_skia,qrealka/skia-hc,Igalia/skia,YUPlayGodDev/platform_external_skia,DARKPOP/external_chromium_org_third_party_skia,MinimalOS/android_external_chromium_org_third_party_skia,w3nd1go/android_external_skia,OptiPop/external_chromium_org_third_party_skia,google/skia,Omegaphora/external_chromium_org_third_party_skia,Igalia/skia,MIPS/external-chromium_org-third_party-skia,MonkeyZZZZ/platform_external_skia,MIPS/external-chromium_org-third_party-skia,xin3liang/platform_external_chromium_org_third_party_skia,xin3liang/platform_external_chromium_org_third_party_skia,Infinitive-OS/platform_external_skia,aosp-mirror/platform_external_skia,ominux/skia,AOSP-YU/platform_external_skia,PAC-ROM/android_external_skia,MarshedOut/android_external_skia,MarshedOut/android_external_skia,spezi77/android_external_skia,chenlian2015/skia_from_google,MinimalOS/external_chromium_org_third_party_skia,mydongistiny/external_chromium_org_third_party_skia,PAC-ROM/android_external_skia,scroggo/skia,Fusion-Rom/external_chromium_org_third_party_skia,pcwalton/skia,MyAOSP/external_chromium_org_third_party_skia,MinimalOS-AOSP/platform_external_skia,MinimalOS-AOSP/platform_external_skia,android-ia/platform_external_chromium_org_third_party_skia,ench0/external_chromium_org_third_party_skia,TeamEOS/external_chromium_org_third_party_skia,timduru/platform-external-skia,shahrzadmn/skia,AOSPB/external_skia,w3nd1go/android_external_skia,TeamExodus/external_skia,TeamExodus/external_skia,pcwalton/skia,timduru/platform-external-skia,Hikari-no-Tenshi/android_external_skia,timduru/platform-external-skia,TeamTwisted/external_skia,DiamondLovesYou/skia-sys,aosp-mirror/platform_external_skia,boulzordev/android_external_skia,MonkeyZZZZ/platform_external_skia,nvoron23/skia,noselhq/skia,pcwalton/skia,Hikari-no-Tenshi/android_external_skia,MinimalOS/android_external_chromium_org_third_party_skia,MonkeyZZZZ/platform_external_skia,MinimalOS/external_chromium_org_third_party_skia,MinimalOS/android_external_chromium_org_third_party_skia,ench0/external_chromium_org_third_party_skia,ench0/external_chromium_org_third_party_skia,rubenvb/skia,amyvmiwei/skia,HalCanary/skia-hc,samuelig/skia,MIPS/external-chromium_org-third_party-skia,qrealka/skia-hc,MinimalOS-AOSP/platform_external_skia,Jichao/skia,TeamTwisted/external_skia,Omegaphora/external_chromium_org_third_party_skia,TeamTwisted/external_skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,android-ia/platform_external_chromium_org_third_party_skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,spezi77/android_external_skia,Fusion-Rom/external_chromium_org_third_party_skia,TeamExodus/external_skia,Hikari-no-Tenshi/android_external_skia,VRToxin-AOSP/android_external_skia,PAC-ROM/android_external_skia,OptiPop/external_chromium_org_third_party_skia,FusionSP/external_chromium_org_third_party_skia,AOSP-YU/platform_external_skia,todotodoo/skia,MinimalOS-AOSP/platform_external_skia,MonkeyZZZZ/platform_external_skia,YUPlayGodDev/platform_external_skia,pcwalton/skia,MinimalOS/external_chromium_org_third_party_skia,invisiblek/android_external_skia,nfxosp/platform_external_skia,UBERMALLOW/external_skia,timduru/platform-external-skia,ominux/skia,jtg-gg/skia,DiamondLovesYou/skia-sys,amyvmiwei/skia,YUPlayGodDev/platform_external_skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,mydongistiny/external_chromium_org_third_party_skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,BrokenROM/external_skia,Jichao/skia,HalCanary/skia-hc,boulzordev/android_external_skia,amyvmiwei/skia,DARKPOP/external_chromium_org_third_party_skia,TeamEOS/external_chromium_org_third_party_skia,jtg-gg/skia,MonkeyZZZZ/platform_external_skia,UBERMALLOW/external_skia,DiamondLovesYou/skia-sys,MinimalOS-AOSP/platform_external_skia,samuelig/skia,MyAOSP/external_chromium_org_third_party_skia,todotodoo/skia,MonkeyZZZZ/platform_external_skia,vanish87/skia,AOSP-YU/platform_external_skia,vanish87/skia,UBERMALLOW/external_skia,MarshedOut/android_external_skia,VRToxin-AOSP/android_external_skia,Infinitive-OS/platform_external_skia,shahrzadmn/skia,Fusion-Rom/external_chromium_org_third_party_skia,TeamEOS/external_chromium_org_third_party_skia,MinimalOS/android_external_chromium_org_third_party_skia,DiamondLovesYou/skia-sys,FusionSP/external_chromium_org_third_party_skia,Omegaphora/external_chromium_org_third_party_skia,chenlian2015/skia_from_google,Hikari-no-Tenshi/android_external_skia,mydongistiny/external_chromium_org_third_party_skia,vanish87/skia,nfxosp/platform_external_skia,TeamExodus/external_skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,nfxosp/platform_external_skia,amyvmiwei/skia,AOSP-YU/platform_external_skia,vanish87/skia,TeamTwisted/external_skia,todotodoo/skia,AOSPB/external_skia,boulzordev/android_external_skia,BrokenROM/external_skia,Jichao/skia,aosp-mirror/platform_external_skia,android-ia/platform_external_chromium_org_third_party_skia,DiamondLovesYou/skia-sys,jtg-gg/skia,DiamondLovesYou/skia-sys,nfxosp/platform_external_skia,google/skia,MarshedOut/android_external_skia,Igalia/skia,TeamExodus/external_skia,todotodoo/skia,android-ia/platform_external_chromium_org_third_party_skia,rubenvb/skia,amyvmiwei/skia,MonkeyZZZZ/platform_external_skia,PAC-ROM/android_external_skia,rubenvb/skia,OneRom/external_skia,Igalia/skia,Infinitive-OS/platform_external_skia,todotodoo/skia,Fusion-Rom/external_chromium_org_third_party_skia,w3nd1go/android_external_skia,aosp-mirror/platform_external_skia,shahrzadmn/skia,FusionSP/external_chromium_org_third_party_skia,noselhq/skia,nfxosp/platform_external_skia,nvoron23/skia,OneRom/external_skia,Infinitive-OS/platform_external_skia,jtg-gg/skia,todotodoo/skia,Igalia/skia,MinimalOS-AOSP/platform_external_skia,MIPS/external-chromium_org-third_party-skia,android-ia/platform_external_chromium_org_third_party_skia,MinimalOS/external_chromium_org_third_party_skia,OptiPop/external_chromium_org_third_party_skia,OneRom/external_skia,BrokenROM/external_skia,HalCanary/skia-hc,tmpvar/skia.cc,UBERMALLOW/external_skia,scroggo/skia,vanish87/skia,tmpvar/skia.cc,nvoron23/skia,qrealka/skia-hc,noselhq/skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,w3nd1go/android_external_skia,Infinitive-OS/platform_external_skia,boulzordev/android_external_skia,AOSPB/external_skia,chenlian2015/skia_from_google,google/skia,OneRom/external_skia,TeamEOS/external_chromium_org_third_party_skia,geekboxzone/mmallow_external_skia,xin3liang/platform_external_chromium_org_third_party_skia,amyvmiwei/skia,Omegaphora/external_chromium_org_third_party_skia,tmpvar/skia.cc,noselhq/skia,MyAOSP/external_chromium_org_third_party_skia,FusionSP/external_chromium_org_third_party_skia,FusionSP/external_chromium_org_third_party_skia,TeamExodus/external_skia,Infinitive-OS/platform_external_skia,MIPS/external-chromium_org-third_party-skia,MinimalOS/android_external_chromium_org_third_party_skia,OneRom/external_skia,Fusion-Rom/external_chromium_org_third_party_skia,google/skia,jtg-gg/skia,scroggo/skia,MyAOSP/external_chromium_org_third_party_skia,MinimalOS/external_chromium_org_third_party_skia,Omegaphora/external_chromium_org_third_party_skia,Omegaphora/external_chromium_org_third_party_skia,TeamTwisted/external_skia,Hikari-no-Tenshi/android_external_skia,vanish87/skia,amyvmiwei/skia,MarshedOut/android_external_skia,OneRom/external_skia,YUPlayGodDev/platform_external_skia,MinimalOS/android_external_chromium_org_third_party_skia,scroggo/skia,Infinitive-OS/platform_external_skia,qrealka/skia-hc,w3nd1go/android_external_skia,HalCanary/skia-hc,VRToxin-AOSP/android_external_skia,shahrzadmn/skia,AOSPB/external_skia,samuelig/skia,geekboxzone/lollipop_external_chromium_org_third_party_skia,MyAOSP/external_chromium_org_third_party_skia,noselhq/skia,nfxosp/platform_external_skia,MarshedOut/android_external_skia,spezi77/android_external_skia,PAC-ROM/android_external_skia,mydongistiny/external_chromium_org_third_party_skia,MIPS/external-chromium_org-third_party-skia,aosp-mirror/platform_external_skia,tmpvar/skia.cc,PAC-ROM/android_external_skia,TeamEOS/external_chromium_org_third_party_skia,MinimalOS-AOSP/platform_external_skia,scroggo/skia,chenlian2015/skia_from_google,MIPS/external-chromium_org-third_party-skia,shahrzadmn/skia,MIPS/external-chromium_org-third_party-skia,PAC-ROM/android_external_skia,DARKPOP/external_chromium_org_third_party_skia,DiamondLovesYou/skia-sys,MyAOSP/external_chromium_org_third_party_skia,geekboxzone/mmallow_external_skia,ominux/skia,Fusion-Rom/external_chromium_org_third_party_skia,vanish87/skia,qrealka/skia-hc,ench0/external_chromium_org_third_party_skia,rubenvb/skia,mydongistiny/external_chromium_org_third_party_skia,boulzordev/android_external_skia,nvoron23/skia,pcwalton/skia,xin3liang/platform_external_chromium_org_third_party_skia,AOSP-YU/platform_external_skia,noselhq/skia,geekboxzone/mmallow_external_skia,VRToxin-AOSP/android_external_skia,UBERMALLOW/external_skia,aosp-mirror/platform_external_skia,invisiblek/android_external_skia,VRToxin-AOSP/android_external_skia,mydongistiny/external_chromium_org_third_party_skia,w3nd1go/android_external_skia,vanish87/skia,invisiblek/android_external_skia,shahrzadmn/skia,rubenvb/skia,ominux/skia,scroggo/skia,YUPlayGodDev/platform_external_skia,samuelig/skia,Igalia/skia,AOSP-YU/platform_external_skia,rubenvb/skia,samuelig/skia,AOSPB/external_skia,rubenvb/skia,pcwalton/skia,google/skia,ench0/external_chromium_org_third_party_skia,android-ia/platform_external_chromium_org_third_party_skia,Fusion-Rom/external_chromium_org_third_party_skia,timduru/platform-external-skia,AOSPB/external_skia,TeamTwisted/external_skia,AOSPB/external_skia,YUPlayGodDev/platform_external_skia,nvoron23/skia,HalCanary/skia-hc,HalCanary/skia-hc,UBERMALLOW/external_skia,MonkeyZZZZ/platform_external_skia,geekboxzone/mmallow_external_skia,MarshedOut/android_external_skia,aosp-mirror/platform_external_skia,xin3liang/platform_external_chromium_org_third_party_skia,OptiPop/external_chromium_org_third_party_skia,BrokenROM/external_skia,pcwalton/skia,tmpvar/skia.cc,spezi77/android_external_skia,TeamTwisted/external_skia,UBERMALLOW/external_skia,OptiPop/external_chromium_org_third_party_skia,ench0/external_chromium_org_third_party_skia,OptiPop/external_chromium_org_third_party_skia,scroggo/skia,aosp-mirror/platform_external_skia