Fixed missing PlaceholderAvatarImage.

ElementX/Sources/Services/Timeline/TimelineItems/Views/PlaceholderAvatarImage.swift

@@ -0,0 +1,43 @@
+// 
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import SwiftUI
+
+struct PlaceholderAvatarImage: View {
+    
+    let firstCharacter: String
+    
+    var body: some View {
+        ZStack {
+            Color(.sRGB, red: 0.05, green: 0.74, blue: 0.55, opacity: 1.0)
+            Text(firstCharacter)
+                .padding(4)
+                .foregroundColor(.white)
+                // Make the text resizable (i.e. Make it large and then allow it to scale down)
+                .font(.system(size: 200))
+                .minimumScaleFactor(0.001)
+        }
+        .aspectRatio(1, contentMode: .fill)
+    }
+}
+
+struct PlaceholderAvatarImage_Previews: PreviewProvider {
+    static var previews: some View {
+        PlaceholderAvatarImage(firstCharacter: "X")
+            .clipShape(Circle())
+            .frame(width: 150, height: 100)
+    }
+}