Merge pull request #697 from Unity-Technologies/Branch_FixDebugMenu

Fixed Lighting Debug panel (issue caused by split of core/hdrp in different assemblies)

ScriptableRenderPipeline/Core/Debugging/DebugMenuManager.cs

         void LookUpDebugPanelClasses()
         {
             // Prepare all debug menus
-            var types = Assembly.GetAssembly(typeof(DebugPanel)).GetTypes()
+            var types = CoreUtils.GetAllAssemblyTypes()
                 .Where(t => t.IsSubclassOf(typeof(DebugPanel)));
 
             m_DebugPanels.Clear();

ScriptableRenderPipeline/HDRenderPipeline/Debug/LightingDebugPanel.cs

         {
             using (new UnityEditor.EditorGUILayout.VerticalScope())
             {
-                m_DebugPanel.GetDebugItem(DebugDisplaySettings.kEnableShadowDebug).handler.OnEditorGUI();
-
                 DebugItem shadowDebug = m_DebugPanel.GetDebugItem(DebugDisplaySettings.kShadowDebugMode);
                 shadowDebug.handler.OnEditorGUI();
                 if ((ShadowMapDebugMode)shadowDebug.GetValue() == ShadowMapDebugMode.VisualizeShadowMap)