Fixes GCD when 1 sec or shorter.

Support aura reducing GCD (SPELLMOD_GLOBAL_COOLDOWN) (e.g. Backdraft, Unholy presence).
Fixes issue #1666.
Fixes issue #1616.

--HG--
branch : trunk

src/game/Player.cpp

@@ -22124,19 +22124,21 @@ void Player::UpdateCharmedAI()
     }
 }
 
-void Player::AddGlobalCooldown(SpellEntry const *spellInfo, Spell const *spell)
+void Player::AddGlobalCooldown(SpellEntry const *spellInfo, Spell *spell)
 {
     if (!spellInfo || !spellInfo->StartRecoveryTime)
         return;
 
-    uint32 cdTime = spellInfo->StartRecoveryTime;
+    float cdTime = float(spellInfo->StartRecoveryTime);
 
     if (!(spellInfo->Attributes & (SPELL_ATTR_UNK4|SPELL_ATTR_PASSIVE)))
         cdTime *= GetFloatValue(UNIT_MOD_CAST_SPEED);
     else if (IsRangedWeaponSpell(spellInfo) && !spell->IsAutoRepeat())
         cdTime *= m_modAttackSpeedPct[RANGED_ATTACK];
 
-    m_globalCooldowns[spellInfo->StartRecoveryCategory] = ((cdTime < 1000 || cdTime > 2000) ? 1000 : cdTime);
+    ApplySpellMod(spellInfo->Id, SPELLMOD_GLOBAL_COOLDOWN, cdTime, spell);
+    if (cdTime > 0)
+        m_globalCooldowns[spellInfo->StartRecoveryCategory] = uint32(cdTime);
 }
 
 bool Player::HasGlobalCooldown(SpellEntry const *spellInfo) const

src/game/Player.h

@@ -1637,7 +1637,7 @@ class Player : public Unit, public GridObject<Player>
         void UpdatePotionCooldown(Spell* spell = NULL);
 
         // global cooldown
-        void AddGlobalCooldown(SpellEntry const *spellInfo, Spell const *spell);
+        void AddGlobalCooldown(SpellEntry const *spellInfo, Spell *spell);
         bool HasGlobalCooldown(SpellEntry const *spellInfo) const;
         void RemoveGlobalCooldown(SpellEntry const *spellInfo);
 

src/game/Unit.h

@@ -109,7 +109,7 @@ enum SpellModOp
     SPELLMOD_CHANCE_OF_SUCCESS      = 18,
     SPELLMOD_ACTIVATION_TIME        = 19,
     SPELLMOD_EFFECT_PAST_FIRST      = 20,
-    SPELLMOD_GLOBAL_COOLDOWN        = 21, //TODO: GCD is not checked by server currently
+    SPELLMOD_GLOBAL_COOLDOWN        = 21,
     SPELLMOD_DOT                    = 22,
     SPELLMOD_EFFECT3                = 23,
     SPELLMOD_SPELL_BONUS_DAMAGE     = 24,