Re-land: Toggle spoken feedback if two fingers are held down.

ash/common/default_accessibility_delegate.cc

Index: ash/common/default_accessibility_delegate.cc
diff --git a/ash/common/default_accessibility_delegate.cc b/ash/common/default_accessibility_delegate.cc
index a4ebb236ba1d80ff9f1a36dcdfbc4d5751bd025c..6a1bd37b533a239a73267a72f67ba76ed05d9b29 100644
--- a/ash/common/default_accessibility_delegate.cc
+++ b/ash/common/default_accessibility_delegate.cc
@@ -146,6 +146,13 @@ AccessibilityAlert DefaultAccessibilityDelegate::GetLastAccessibilityAlert() {
   return accessibility_alert_;
 }
 
+bool DefaultAccessibilityDelegate::ShouldToggleSpokenFeedbackViaTouch() {
+  return false;
+}
+
+void DefaultAccessibilityDelegate::PlaySpokenFeedbackToggleCountdown(
+    int tick_count) {}
+
 void DefaultAccessibilityDelegate::PlayEarcon(int sound_key) {}
 
 base::TimeDelta DefaultAccessibilityDelegate::PlayShutdownSound() const {