[CRD iOS] Add support for three-finger gestures

remoting/ios/app/host_view_controller.mm

Index: remoting/ios/app/host_view_controller.mm
diff --git a/remoting/ios/app/host_view_controller.mm b/remoting/ios/app/host_view_controller.mm
index 9fd272d06f1e2f708d50beac1797801432f729b9..07fa9f4968f1ea1b2eaf165dbd9e4281b063699c 100644
--- a/remoting/ios/app/host_view_controller.mm
+++ b/remoting/ios/app/host_view_controller.mm
@@ -24,7 +24,8 @@
 static const CGFloat kFabInset = 15.f;
 static const CGFloat kKeyboardAnimationTime = 0.3;
 
-@interface HostViewController ()<ClientKeyboardDelegate> {
+@interface HostViewController ()<ClientKeyboardDelegate,
+                                 ClientGesturesDelegate> {
   RemotingClient* _client;
   MDCFloatingButton* _floatingButton;
   ClientGestures* _clientGestures;
@@ -100,6 +101,7 @@ static const CGFloat kKeyboardAnimationTime = 0.3;
 
   _clientGestures =
       [[ClientGestures alloc] initWithView:self.view client:_client];
+  _clientGestures.delegate = self;
   [[NSNotificationCenter defaultCenter]
       addObserver:self
          selector:@selector(keyboardWillShow:)
@@ -200,6 +202,16 @@ static const CGFloat kKeyboardAnimationTime = 0.3;
   _client.keyboardInterpreter->HandleDeleteEvent(0);
 }
 
+#pragma mark - ClientGesturesDelegate
+
+- (void)keyboardShouldShow {
+  [self showKeyboard];
+}
+
+- (void)keyboardShouldHide {
+  [self hideKeyboard];
+}
+
 #pragma mark - Private
 
 - (void)didTap:(id)sender {