Fixed _ScreenParams after upscaling and update screen node doc

As in title

Author: alelievr

Packages/com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/HDRenderPipeline.RenderGraph.cs

@@ -2329,7 +2329,9 @@ void ResetCameraDataAfterPostProcess(RenderGraph renderGraph, HDCamera hdCamera,
                     builder.SetRenderFunc(
                         (ResetCameraSizeForAfterPostProcessPassData data, RenderGraphContext ctx) =>
                         {
-                            data.shaderVariablesGlobal._ScreenSize = new Vector4(data.hdCamera.finalViewport.width, data.hdCamera.finalViewport.height, 1.0f / data.hdCamera.finalViewport.width, 1.0f / data.hdCamera.finalViewport.height);
+                            var screenSize = new Vector4(data.hdCamera.finalViewport.width, data.hdCamera.finalViewport.height, 1.0f / data.hdCamera.finalViewport.width, 1.0f / data.hdCamera.finalViewport.height);
+                            data.shaderVariablesGlobal._ScreenSize = screenSize;
+                            data.shaderVariablesGlobal._ScreenParams = new Vector4(screenSize.x, screenSize.y, 1 + screenSize.z, 1 + screenSize.w);
                             data.shaderVariablesGlobal._RTHandleScale = RTHandles.rtHandleProperties.rtHandleScale;
                             data.hdCamera.UpdateGlobalMipBiasCB(ref data.shaderVariablesGlobal, 0);
                             ConstantBuffer.PushGlobal(ctx.cmd, data.shaderVariablesGlobal, HDShaderIDs._ShaderVariablesGlobal);

Packages/com.unity.shadergraph/Documentation~/Screen-Node.md

@@ -7,7 +7,7 @@ Provides access to parameters of the screen.
 #### Unity Render Pipelines Support
 - Universal Render Pipeline
 
-The High Definition Render Pipeline does **not** support this Node.
+Note: when dynamic resolution is enabled, this node will return the current viewport of the rendering camera. After the upscaling pass, the output of this node will be equal to the screen size.
 
 ## Ports