Add call link details screen scaffolding.

app/src/main/java/org/thoughtcrime/securesms/conversation/colors/AvatarColorPair.kt

@@ -29,4 +29,22 @@ class AvatarColorPair private constructor(
       }
     }
   }
+
+  override fun equals(other: Any?): Boolean {
+    if (this === other) return true
+    if (javaClass != other?.javaClass) return false
+
+    other as AvatarColorPair
+
+    if (foregroundColor != other.foregroundColor) return false
+    if (backgroundColor != other.backgroundColor) return false
+
+    return true
+  }
+
+  override fun hashCode(): Int {
+    var result = foregroundColor
+    result = 31 * result + backgroundColor
+    return result
+  }
 }