Fixed scaling issue with camera viewport

com.unity.render-pipelines.lightweight/LWRP/Passes/ForwardLitPass.cs

 
                 // If rendering to an intermediate RT we resolve viewport on blit due to offset not being supported
                 // while rendering to a RT.
-                if (colorAttachmentHandle == -1 && cameraData.isDefaultViewport)
+                if (colorAttachmentHandle == -1 && !cameraData.isDefaultViewport)
                     cmd.SetViewport(camera.pixelRect);
 
                 context.ExecuteCommandBuffer(cmd);
             CommandBuffer cmd = CommandBufferPool.Get("Final Blit Pass");
             cmd.SetGlobalTexture("_BlitTex", sourceRT);
 
-            if (!cameraData.isDefaultViewport)
+            // We need to handle viewport on a RT. We do it by rendering a fullscreen quad + viewport
+            if (colorAttachmentHandle != -1 && !cameraData.isDefaultViewport)
+                
             }
             else
             {