Rename "HomogeneousMediumVolume" to "HomogeneousDensityVolume"

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Lighting/Volumetrics/HomogeneousMediumVolume.cs

 {
     [ExecuteInEditMode]
     [AddComponentMenu("RenderPipeline/High Definition/Homogeneous Medium Volume", -1)]
-    public class HomogeneousMediumVolume : MonoBehaviour
+    public class HomogeneousDensityVolume : MonoBehaviour
     {
         public VolumeParameters volumeParameters = new VolumeParameters();
 
         }
 
         // Returns NULL if a global fog component does not exist, or is not enabled.
-        public static HomogeneousMediumVolume GetGlobalHomogeneousMediumVolume()
+        public static HomogeneousDensityVolume GetGlobalHomogeneousDensityVolume()
-            HomogeneousMediumVolume globalVolume = null;
+            HomogeneousDensityVolume globalVolume = null;
-            HomogeneousMediumVolume[] volumes = FindObjectsOfType(typeof(HomogeneousMediumVolume)) as HomogeneousMediumVolume[];
+            HomogeneousDensityVolume[] volumes = FindObjectsOfType(typeof(HomogeneousDensityVolume)) as HomogeneousDensityVolume[];
-            foreach (HomogeneousMediumVolume volume in volumes)
+            foreach (HomogeneousDensityVolume volume in volumes)
             {
                 if (volume.enabled && !volume.volumeParameters.IsLocalVolume())
                 {

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Lighting/Volumetrics/VolumetricLighting.cs

     {
         if (preset == VolumetricLightingPreset.Off) return;
 
-        HomogeneousMediumVolume globalVolume = HomogeneousMediumVolume.GetGlobalHomogeneousMediumVolume();
+        HomogeneousDensityVolume globalVolume = HomogeneousDensityVolume.GetGlobalHomogeneousDensityVolume();
 
         // TODO: may want to cache these results somewhere.
         VolumeProperties globalVolumeProperties = (globalVolume != null) ? globalVolume.volumeParameters.GetProperties()
         m_VisibleVolumeProperties.Clear();
 
         // Collect all the visible volume data, and upload it to the GPU.
-        HomogeneousMediumVolume[] volumes = Object.FindObjectsOfType(typeof(HomogeneousMediumVolume)) as HomogeneousMediumVolume[];
+        HomogeneousDensityVolume[] volumes = Object.FindObjectsOfType(typeof(HomogeneousDensityVolume)) as HomogeneousDensityVolume[];
-        foreach (HomogeneousMediumVolume volume in volumes)
+        foreach (HomogeneousDensityVolume volume in volumes)
         {
             // Only test active finite volumes.
             if (volume.enabled && volume.volumeParameters.IsLocalVolume())
             VBuffer vBuffer = FindVBuffer(camera.GetViewID());
             Debug.Assert(vBuffer != null);
 
-            HomogeneousMediumVolume globalVolume = HomogeneousMediumVolume.GetGlobalHomogeneousMediumVolume();
+            HomogeneousDensityVolume globalVolume = HomogeneousDensityVolume.GetGlobalHomogeneousDensityVolume();
             float asymmetry = globalVolume != null ? globalVolume.volumeParameters.asymmetry : 0;
 
             if (globalVolume == null)