Optimize two vectors in alpha draw pool by making them static and clearing at...

Optimize two vectors in alpha draw pool by making them static and clearing at end of draw, this avoids thousands of mallocs

indra/newview/lldrawpoolalpha.cpp

@@ -628,8 +628,8 @@ void LLDrawPoolAlpha::renderAlpha(U32 mask, S32 pass)
 		if (group->getSpatialPartition()->mRenderByGroup &&
 		    !group->isDead())
 		{
-            std::vector<LLDrawInfo*> emissives;
-            std::vector<LLDrawInfo*> fullbrights;
+            static std::vector<LLDrawInfo*> emissives;
+            static std::vector<LLDrawInfo*> fullbrights;
 
 			bool is_particle_or_hud_particle = group->getSpatialPartition()->mPartitionType == LLViewerRegion::PARTITION_PARTICLE
 													  || group->getSpatialPartition()->mPartitionType == LLViewerRegion::PARTITION_HUD_PARTICLE;
@@ -849,6 +849,9 @@ void LLDrawPoolAlpha::renderAlpha(U32 mask, S32 pass)
             {
                 current_shader->bind();
             }
+
+			emissives.clear();
+			fullbrights.clear();
 		}        
 	}