Fix issue with framesettings on HDRP Asset and debug windows

When the debug windows is open, the HDRP Asset runtime framesetting are
overwritten by the debug windows settings, whereas it is the debug
windows that should update itself.

ScriptableRenderPipeline/Core/CoreRP/Debugging/DebugManager.cs

 
     public sealed partial class DebugManager
     {
+#if UNITY_EDITOR
+        // HACK: Make debug windows work correctly with FrameSettings in Editor
+        public static bool renderPipelineIsRecreated = false;
+#endif
+
         static readonly DebugManager s_Instance = new DebugManager();
         public static DebugManager instance { get { return s_Instance; } }
 

ScriptableRenderPipeline/Core/CoreRP/Editor/Debugging/DebugWindow.cs

             DebugManager.instance.onSetDirty -= MarkDirty;
             Undo.ClearUndo(m_Settings);
 
+            DestroyWidgetStates();
+        }
+
+        public void DestroyWidgetStates()
+        {
             if (m_WidgetStates != null)
             {
                 // Clear all the states from memory
 
         void Update()
         {
+            // HACK: Make debug windows work correctly with FrameSettings in Editor
+            // When we manipulate the framesettings on HDRenderPipelineAsset, the debug windows is not
+            // refresh, it keep the old state of the runtime framesettings in memory and thus overwrite
+            // our freshly edited value. To ensure debug windows is aware of framesettings change we need to
+            // destroy its internal widget state.
+            if (DebugManager.renderPipelineIsRecreated)
+            {
+                DestroyWidgetStates();
+                DebugManager.renderPipelineIsRecreated = false;
+            }
+            // END HACK
+
             int treeState = DebugManager.instance.GetState();
 
             if (m_DebugTreeState != treeState || m_IsDirty)

ScriptableRenderPipeline/HDRenderPipeline/HDRP/HDRenderPipeline.cs

 
         public HDRenderPipeline(HDRenderPipelineAsset asset)
         {
+#if UNITY_EDITOR
+            // HACK: Make debug windows work correctly with FrameSettings in Editor
+            DebugManager.renderPipelineIsRecreated = true;
+#endif
+
             m_ValidAPI = true;
 
             if (!SetRenderingFeatures())