scale xmin and xmax for FontMetrics
scale xmin and xmax for FontMetrics

BUG=skia:

Review URL: https://codereview.chromium.org/685153004

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