Fix build

submodules/Speak/BUILD

@@ -0,0 +1,15 @@
+load("@build_bazel_rules_swift//swift:swift.bzl", "swift_library")
+
+swift_library(
+    name = "Speak",
+    module_name = "Speak",
+    srcs = glob([
+        "Sources/**/*.swift",
+    ]),
+    deps = [
+        "//submodules/Display:Display",
+    ],
+    visibility = [
+        "//visibility:public",
+    ],
+)

submodules/Speak/Sources/Speak.swift

@@ -0,0 +1,18 @@
+import Foundation
+import AVFoundation
+
+// Incuding at least one Objective-C class in a swift file ensures that it doesn't get stripped by the linker
+private final class LinkHelperClass: NSObject {
+}
+
+public func speakText(_ text: String) {
+    guard !text.isEmpty else {
+        return
+    }
+    let speechSynthesizer = AVSpeechSynthesizer()
+    let utterance = AVSpeechUtterance(string: text)
+    if #available(iOS 11.0, *), let language = NSLinguisticTagger.dominantLanguage(for: text) {
+        utterance.voice = AVSpeechSynthesisVoice(language: language)
+    }
+    speechSynthesizer.speak(utterance)
+}