World|Client: Schedule missing material fixes in ClientSubsector

ClientSubsector is the first to know about any changes to subspace
geometry so scheduling of missing material fixes should be done here
as those notifications are inherently "localized , or scoped" to a map
space subregion (the extra info should mean updates can be targeted
directly and incorporated into support for id Tech 1 mapping hacks).

Previously, Sector handled this by simply observing it's planes and
then attempting a fix for both sides of every Line which references
the Sector.

doomsday/apps/client/src/client/clientsubsector.cpp

@@ -1179,6 +1179,19 @@ DENG2_PIMPL(ClientSubsector)
         }
     }
 
+    /**
+     * @todo Optimize: Target and process only the dependent surfaces -ds
+     */
+    void fixSurfacesMissingMaterials()
+    {
+        self.sector().forAllSides([] (LineSide &side)
+        {
+            side.fixSurfacesMissingMaterials();
+            side.back().fixSurfacesMissingMaterials();
+            return LoopContinue;
+        });
+    }
+
     /// Observes Line FlagsChange
     void lineFlagsChanged(Line &line, dint oldFlags)
     {
@@ -1233,6 +1246,9 @@ DENG2_PIMPL(ClientSubsector)
         // We may need to update one or both mapped planes.
         maybeInvalidateMapping(plane.indexInSector());
 
+        // We may need to fix newly revealed missing materials.
+        fixSurfacesMissingMaterials();
+
         // We may need to project new decorations.
         markDependentSurfacesForRedecoration(plane);
 

doomsday/apps/client/src/world/base/sector.cpp

@@ -214,23 +214,9 @@ DENG2_PIMPL(Sector)
         updateSideEmitterOrigins();
     }
 
-#ifdef __CLIENT__
-    void fixSurfacesMissingMaterials()
-    {
-        for (LineSide *side : sides)
-        {
-            side->fixSurfacesMissingMaterials();
-            side->back().fixSurfacesMissingMaterials();
-        }
-    }
-#endif
-
     void planeHeightChanged(Plane &)
     {
         updateAllSideEmitterOrigins();
-#ifdef __CLIENT__
-        fixSurfacesMissingMaterials();
-#endif
     }
 
     DENG2_PIMPL_AUDIENCE(LightLevelChange)