Fix float serialization in Constant Node to not be affected by system locale (was comma as decimal separator causing shader errors)

com.unity.shadergraph/Editor/Data/Nodes/Input/Basic/ConstantNode.cs

 using System.Collections.Generic;
+using System.Globalization;
 using UnityEditor.ShaderGraph.Drawing.Controls;
 using UnityEngine;
 using UnityEditor.Graphing;
 
         public void GenerateNodeCode(ShaderGenerator visitor, GenerationMode generationMode)
         {
-            visitor.AddShaderChunk(precision + " " + GetVariableNameForNode() + " = " + m_constantList[constant] + ";", true);
+            visitor.AddShaderChunk(precision + " " + GetVariableNameForNode() + " = " + m_constantList[constant].ToString(CultureInfo.InvariantCulture) + ";", true);
         }
 
         public override string GetVariableNameForSlot(int slotId)

com.unity.shadergraph/Editor/Drawing/PreviewManager.cs

                                 try
                                 {
                                     node = results.sourceMap.FindNode(error.line);
+                                    message.AppendLine("Shader compilation error in {3} at line {1} (on {2}):\n{0}", error.message, error.line, error.platform, node != null ? string.Format("node {0} ({1})", node.name, node.guid) : "graph");
+                                    message.AppendLine(error.messageDetails);
+                                    message.AppendNewLine();
-                                catch (Exception e)
+                                catch
-                                    Debug.LogException(e);
-                                    continue;
+                                    message.AppendLine("Shader compilation error in {3} at line {1} (on {2}):\n{0}", error.message, error.line, error.platform, "graph");
-                                message.AppendLine("{0} in {3} at line {1} (on {2})", error.message, error.line, error.platform, node != null ? string.Format("node {0} ({1})", node.name, node.guid) : "graph");
-                                message.AppendLine(error.messageDetails);
-                                message.AppendNewLine();
                             }
                             Debug.LogWarning(message.ToString());
                             ShaderUtil.ClearShaderErrors(m_UberShader);