Error if ClassColorsBlizz enabled but not ClassColors

[Sapu94]

The former references CUSTOM_CLASS_COLORS which is created by the latter. So, if just the former is enabled, you'll get an error when trying to access that global. Here's a trimmed-down version of the error report I ended up getting from a user as a result:

Message: ...erface/AddOns/!ClassColorsBlizz/ClassColorsBlizz.lua:400: attempt to index global 'CUSTOM_CLASS_COLORS' (a nil value)
Time: 05/21/18 17:54:16 (9798718)
Client: 7.3.5
Locale: enUS
Combat: false
Error Count: 1
Stack Trace:
    erface/AddOns/!ClassColorsBlizz/ClassColorsBlizz.lua:400: <AddMessage>
    TSM/Core/Lib/Addon.lua:138: <Addon.lua:137>
    TSM/Core/Lib/Addon.lua:147: <Addon.lua:145>
    TSM/Core/Lib/Addon.lua:151: <Addon.lua:150>
    TSM/Old_Modules/Mailing/Inbox.lua:577: <PrintOpenMailMessage>
    TSM/Old_Modules/Mailing/Inbox.lua:633: <Inbox.lua:592>
    TSM/Core/Lib/Threading.lua:499: <Threading.lua:496>
Addons:
    Altoholic (r183)
    Auctionator (4.0.19)
    !ClassColorsBlizz (7.3.5.1)
    ConsLegion (1.28)
    DataStore (r64)
    Details ()
    Details_DmgRank ()
    Details_DeathGraphs ()
    Details_DpsTuning ()
    Details_EncounterDetails ()
    Details_RaidCheck ()
    Details_TimeAttack ()
    Details_TinyThreat ()
    Details_Vanguard ()
    Details_Streamer ()
    Details_RaidInfo-EmeraldNightmare ()
    Details_RaidInfo-Nighthold ()
    Details_RaidInfo-TombOfSargeras ()
    Details_RaidInfo-TrialOfValor ()
    Details_ChartViewer ()
    Dominos (7.3.2)
    DontCast (1.4.2)
    HHTD (2.4.6)
    Jamba (5.4.1)
    PartyAbilityBars ()
    TalentSetManager ()
    TomTom (v70300-1.0.0)
    TSM (815786a)
    TSM_AppHelper (a8f2b46)

Addon.lua:138 is doing DEFAULT_CHAT_FRAME:AddMessage("...")

[Phanx]

Fixed lazily in e3487ae