Resolve suppressed IDE0031 warnings (#10812)

Those were temporarily suppressed in 90cfb1a
I used Visual Studio to fix all of them automatically.

Author: ViktorHofer

Directory.Build.props

@@ -6,8 +6,6 @@
     <TargetFramework>net10.0</TargetFramework>
     <TargetFrameworkVersion>10.0</TargetFrameworkVersion>
     <BuildWithNetFrameworkHostedCompiler>true</BuildWithNetFrameworkHostedCompiler>
-    <!-- Temporarily disable IDE0031: Null check can be simplified warnings. -->
-    <NoWarn>$(NoWarn);IDE0031</NoWarn>
   </PropertyGroup>
   <!-- Normalize $(TestWpfArcadeSdkPath) by appending a '\' to it if one is missing -->
   <PropertyGroup Condition="'$(TestWpfArcadeSdkPath)'!=''">

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Annotations/Component/AnnotationHighlightLayer.cs

@@ -1114,8 +1114,7 @@ protected override Geometry DefiningGeometry
 
                     //reset render transformation of the TopOwner
                     UIElement uie = TopOwner as UIElement;
-                    if (uie != null)
-                        uie.RenderTransform = Transform.Identity;
+                    uie?.RenderTransform = Transform.Identity;
 
                     return geometry;
                 }

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Annotations/Component/MarkedHighlightComponent.cs

@@ -407,13 +407,10 @@ private void SetMarkerTransform(Path marker, ITextPointer anchor, ITextPointer b
             topTailTransform.Children.Add(tailScale);
             topTailTransform.Children.Add(topOffset);
 
-            if (geometry.Children[0] != null)
-                geometry.Children[0].Transform = topTailTransform;
+            geometry.Children[0]?.Transform = topTailTransform;
 
-            if (geometry.Children[1] != null)
-                geometry.Children[1].Transform = bodyTransform;
-            if (geometry.Children[2] != null)
-                geometry.Children[2].Transform = bottomTailTransform;
+            geometry.Children[1]?.Transform = bodyTransform;
+            geometry.Children[2]?.Transform = bottomTailTransform;
 
             //add transform to base anchor if needed
             if (baseAnchor != null)

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Controls/ActiveXContainer.cs

@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 //
@@ -46,8 +46,7 @@ internal ActiveXContainer(ActiveXHost host)
         //
         int UnsafeNativeMethods.IOleContainer.ParseDisplayName(Object pbc, string pszDisplayName, int[] pchEaten, Object[] ppmkOut)
         {
-            if (ppmkOut != null)
-                ppmkOut[0] = null;
+            ppmkOut?[0] = null;
 
             return NativeMethods.E_NOTIMPL;
         }

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Controls/StickyNote/StickyNoteAnnotations.cs

@@ -1137,8 +1137,7 @@ bool IAnnotationComponent.IsDirty
             }
             set
             {
-                if (_anchor != null)
-                    _anchor.IsDirty = value;
+                _anchor?.IsDirty = value;
                 if (value)
                     InvalidateVisual();
             }

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Data/LiveShapingBlock.cs

@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 //
@@ -26,8 +26,7 @@ internal LiveShapingList List
         public override LiveShapingItem SetItemAt(int offset, LiveShapingItem lsi)
         {
             base.SetItemAt(offset, lsi);
-            if (lsi != null)
-                lsi.Block = this;
+            lsi?.Block = this;
             return lsi;
         }
 

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Data/RBNode.cs

@@ -548,8 +548,8 @@ private RBNode<T> Substitute(RBNode<T> node, RBNode<T> sub, RBNode<T> parent)
             sub.Parent = node.Parent;
             sub.IsRed = node.IsRed;
 
-            if (sub.LeftChild != null) sub.LeftChild.Parent = sub;
-            if (sub.RightChild != null) sub.RightChild.Parent = sub;
+            sub.LeftChild?.Parent = sub;
+            sub.RightChild?.Parent = sub;
             return sub;
         }
 
@@ -624,7 +624,7 @@ private RBNode<T> RotateLeft()
             node.IsRed = this.IsRed;
             node.Parent = this.Parent;
             this.RightChild = node.LeftChild;
-            if (this.RightChild != null) this.RightChild.Parent = this;
+            this.RightChild?.Parent = this;
             node.LeftChild = this;
             this.IsRed = true;
             this.Parent = node;
@@ -638,7 +638,7 @@ private RBNode<T> RotateRight()
             node.IsRed = this.IsRed;
             node.Parent = this.Parent;
             this.LeftChild = node.RightChild;
-            if (this.LeftChild != null) this.LeftChild.Parent = this;
+            this.LeftChild?.Parent = this;
             node.RightChild = this;
             this.IsRed = true;
             this.Parent = node;
@@ -836,8 +836,8 @@ protected RBNode<T> LoadTree(ref string s)
 
             node.LeftChild = LoadTree(ref s);   // read subtrees
             node.RightChild = LoadTree(ref s);
-            if (node.LeftChild != null) node.LeftChild.Parent = node;
-            if (node.RightChild != null) node.RightChild.Parent = node;
+            node.LeftChild?.Parent = node;
+            node.RightChild?.Parent = node;
 
             s = s.Substring(1);             // skip ')'
 

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Data/RBTree.cs

@@ -424,8 +424,7 @@ internal RBNode<T> InsertNode(int index)
         internal void RemoveNode(int index)
         {
             LeftChild = DeleteNode(this, LeftChild, index);
-            if (LeftChild != null)
-                LeftChild.IsRed = false;
+            LeftChild?.IsRed = false;
         }
 
         internal virtual RBNode<T> NewNode()
@@ -500,8 +499,7 @@ public void RemoveAt(int index)
 
             RBFinger<T> finger = FindIndex(index, true);
             RemoveAt(ref finger);
-            if (LeftChild != null)
-                LeftChild.IsRed = false;
+            LeftChild?.IsRed = false;
 
             Verify(size - 1);
         }
@@ -593,8 +591,7 @@ public bool Remove(T item)
             RBFinger<T> finger = Find(item, Comparison);
             if (finger.Found)
                 RemoveAt(ref finger);
-            if (LeftChild != null)
-                LeftChild.IsRed = false;
+            LeftChild?.IsRed = false;
             return finger.Found;
         }
 

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/Printing/PrintDlgExMarshaler.cs

@@ -334,10 +334,7 @@ string printerName
                         }
                     }
                 }
-                if (printQueue != null)
-                {
-                    printQueue.InPartialTrust = true;
-                }
+                printQueue?.InPartialTrust = true;
 
                 return printQueue;
             }

src/Microsoft.DotNet.Wpf/src/PresentationFramework/MS/Internal/PtsHost/ContainerParagraph.cs

@@ -1189,14 +1189,8 @@ private void BuildUpdateRecord()
                 }
                 while (paraInvalid != ur.SyncPara)
                 {
-                    if (paraInvalid.Next != null)
-                    {
-                        paraInvalid.Next.Previous = null;
-                    }
-                    if (paraInvalid.Previous != null)
-                    {
-                        paraInvalid.Previous.Next = null;
-                    }
+                    paraInvalid.Next?.Previous = null;
+                    paraInvalid.Previous?.Next = null;
                     paraInvalid.Dispose();
                     paraInvalid = paraInvalid.Next;
                 }