Merge branch 'widgets_panel' into 'master'

fix sample

See merge request upm-packages/ui-widgets/com.unity.uiwidgets!95

Editor/UIWidgetsPanelEditor.cs

+using Unity.UIWidgets.engine;
+using UnityEditor;
+using UnityEditor.UI;
+
+namespace Unity.UIWidgets.Editor {
+    [CustomEditor(typeof(UIWidgetsPanel), true)]
+    [CanEditMultipleObjects]
+    public class UIWidgetsPanelEditor : RawImageEditor {
+        public override void OnInspectorGUI() {
+            base.OnInspectorGUI();
+            var pixelRatioProperty = this.serializedObject.FindProperty("devicePixelRatioOverride");
+            EditorGUILayout.PropertyField(pixelRatioProperty);
+            this.serializedObject.ApplyModifiedProperties();
+        }
+    }
+}

Editor/UIWidgetsPanelEditor.cs.meta

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+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
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+  icon: {instanceID: 0}
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Samples/UIWidgetsSample.asmdef

+{
+    "name": "UIWidgetsSample",
+    "references": [
+        "Unity.UIWidgets"
+    ],
+    "optionalUnityReferences": [],
+    "includePlatforms": [],
+    "excludePlatforms": [],
+    "allowUnsafeCode": false,
+    "overrideReferences": false,
+    "precompiledReferences": [],
+    "autoReferenced": true,
+    "defineConstraints": []
+}

Samples/UIWidgetsSample.asmdef.meta

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