Merge pull request #201 from UnityTech/yczhang

Cleanup Warnings.

Runtime/debugger/diagnostics.cs

 using Unity.UIWidgets.ui;
 
 namespace Unity.UIWidgets.debugger {
+#pragma warning disable 0659
+#pragma warning disable 0661
     public class DiagnosticsNode : IEquatable<DiagnosticsNode> {
         readonly Dictionary<string, object> _json; // todo use json class such as simple json
         public readonly bool isProperty;
             }
         }
     }
+#pragma warning restore 0659
+#pragma warning restore 0661
 
     public class InspectorInstanceRef : IEquatable<InspectorInstanceRef> {
         public readonly string id;

Runtime/flow/physical_shape_layer.cs

         Color _shadow_color;
         float _device_pixel_ratio;
         Path _path;
+#pragma warning disable 0414
+#pragma warning restore 0414
         Rect _frameRRect;
         Clip _clip_behavior;
 

Runtime/foundation/key.cs

 using System.Collections.Generic;
 
 namespace Unity.UIWidgets.foundation {
+    
+#pragma warning disable 0660
+#pragma warning disable 0661
     public abstract class Key {
         protected Key() {
         }
             return !Equals(left, right);
         }
     }
+#pragma warning restore 0660
+#pragma warning restore 0661
 
     public abstract class LocalKey : Key {
         protected LocalKey() {

Runtime/material/slider_theme.cs

                     return true;
                 }
 
+#pragma warning disable 0162
                 Offset leftCenter = _topLobeCenter - new Offset(leftWidthNeeded, 0.0f) + neckStretch;
                 Offset rightCenter = _topLobeCenter + new Offset(rightWidthNeeded, 0.0f) + neckStretch;
                 Rect valueRect = Rect.fromLTRB(
                 outlinePaint.strokeWidth = 1.0f;
                 canvas.drawRect(valueRect, outlinePaint);
                 return true;
+#pragma warning restore 0162
             });
 
             _addArc(

Runtime/material/text_field.cs

                 formatters.Add(new LengthLimitingTextInputFormatter(this.widget.maxLength));
             }
             
-            bool forcePressEnabled = false;
+            // bool forcePressEnabled = false; // TODO: wait for force press is ready
             TextSelectionControls textSelectionControls = MaterialUtils.materialTextSelectionControls;;
             bool paintCursorAboveText = false;
             bool cursorOpacityAnimates = false;

Runtime/painting/fractional_offset.cs

             get { return (this.y + 1.0f) / 2.0f; }
         }
 
-        public readonly FractionalOffset topLeft = new FractionalOffset(0.0f, 0.0f);
+#pragma warning disable 0108
+        public static readonly FractionalOffset topLeft = new FractionalOffset(0.0f, 0.0f);
-        public readonly FractionalOffset topCenter = new FractionalOffset(0.5f, 0.0f);
+        public static readonly FractionalOffset topCenter = new FractionalOffset(0.5f, 0.0f);
-        public readonly FractionalOffset topRight = new FractionalOffset(1.0f, 0.0f);
+        public static readonly FractionalOffset topRight = new FractionalOffset(1.0f, 0.0f);
-        public readonly FractionalOffset centerLeft = new FractionalOffset(0.0f, 0.5f);
+        public static readonly FractionalOffset centerLeft = new FractionalOffset(0.0f, 0.5f);
-        public readonly FractionalOffset center = new FractionalOffset(0.5f, 0.5f);
+        public static readonly FractionalOffset center = new FractionalOffset(0.5f, 0.5f);
-        public readonly FractionalOffset centerRight = new FractionalOffset(1.0f, 0.5f);
+        public static readonly FractionalOffset centerRight = new FractionalOffset(1.0f, 0.5f);
-        public readonly FractionalOffset bottomLeft = new FractionalOffset(0.0f, 1.0f);
+        public static readonly FractionalOffset bottomLeft = new FractionalOffset(0.0f, 1.0f);
-        public readonly FractionalOffset bottomCenter = new FractionalOffset(0.5f, 1.0f);
+        public static readonly FractionalOffset bottomCenter = new FractionalOffset(0.5f, 1.0f);
-        public readonly FractionalOffset bottomRight = new FractionalOffset(1.0f, 1.0f);
+        public static readonly FractionalOffset bottomRight = new FractionalOffset(1.0f, 1.0f);
+#pragma warning restore 0108
 
         public static Alignment operator -(FractionalOffset a, Alignment b) {
             if (!(b is FractionalOffset)) {

Runtime/rendering/object.mixin.gen.cs

 namespace Unity.UIWidgets.rendering {
 
     public abstract class RenderObjectWithChildMixinRenderObject<ChildType> : RenderObject, RenderObjectWithChildMixin<ChildType>, RenderObjectWithChildMixin where ChildType : RenderObject {
-        public bool debugValidateChild(RenderObject child) {
+        public virtual bool debugValidateChild(RenderObject child) {
             D.assert(() => {
                 if (!(child is ChildType)) {
                     throw new UIWidgetsError(
 
 
     public abstract class RenderObjectWithChildMixinRenderBox<ChildType> : RenderBox, RenderObjectWithChildMixin<ChildType>, RenderObjectWithChildMixin where ChildType : RenderObject {
-        public bool debugValidateChild(RenderObject child) {
+        public virtual bool debugValidateChild(RenderObject child) {
             D.assert(() => {
                 if (!(child is ChildType)) {
                     throw new UIWidgetsError(
             get { return this._childCount; }
         }
 
-        public bool debugValidateChild(RenderObject child) {
+        public override bool debugValidateChild(RenderObject child) {
             D.assert(() => {
                 if (!(child is ChildType)) {
                     throw new UIWidgetsError(

Runtime/rendering/paragraph.cs

         }
 
         TextSpan _previousHoverSpan;
+
+#pragma warning disable 0414
+#pragma warning restore 0414
         bool _hasHoverRecognizer;
         MouseTrackerAnnotation _hoverAnnotation;
 

Runtime/widgets/nested_scroll_view.cs

         ScrollDirection _userScrollDirection = ScrollDirection.idle;
 
         public void updateUserScrollDirection(ScrollDirection value) {
-            D.assert(value != null);
             if (this.userScrollDirection == value) {
                 return;
             }
         }
 
         public override string ToString() {
-            string extra;
+            string extra = "";
             switch (this._writers) {
                 case 0:
                     extra = ", orphan";
                     break;
             }
 
-            return "$GetType()($layoutExtent$extra)";
+            return $"{this.GetType()}({this.layoutExtent}{extra})";
         }
     }
 

Tests/Editor/SceneViewTests.cs

     public class SceneViewTests {
         public static void show() {
             onPreSceneGUIDelegate += OnPreSceneGUI;
+#pragma warning disable 0618
+#pragma warning restore 0618
             EditorApplication.update += Update;
 
             SceneView.RepaintAll();
 
         public static void hide() {
             onPreSceneGUIDelegate -= OnPreSceneGUI;
+#pragma warning disable 0618
+#pragma warning restore 0618
+#pragma warning disable 0618
         public static SceneView.OnSceneFunc onPreSceneGUIDelegate {
             get {
                 var field = typeof(SceneView).GetField("onPreSceneGUIDelegate",
                 field.SetValue(null, value);
             }
         }
+#pragma warning restore 0618
 
         static Func<Widget>[] _options;
 

Tests/Editor/Widgets.cs

         const float headerHeight = 80.0f;
 
         float _offsetY = 0.0f;
+#pragma warning disable 0414
+#pragma warning restore 0414
 
         Widget _buildHeader(BuildContext context) {
             return new Container(