[Remoting iOS] Basic viewport manipulation support

remoting/client/ios/client_gestures.h

Index: remoting/client/ios/client_gestures.h
diff --git a/remoting/client/ios/client_gestures.h b/remoting/client/ios/client_gestures.h
index aea0d3ca352c89b5349bd2175dc21508181ade3e..ab9780d4047a7c13842c2adbbb1fc9fc71c4b68c 100644
--- a/remoting/client/ios/client_gestures.h
+++ b/remoting/client/ios/client_gestures.h
@@ -8,6 +8,7 @@
 #import <Foundation/Foundation.h>
 #import <UIKit/UIKit.h>
 #include "base/logging.h"
+#include "remoting/client/desktop_viewport.h"
 #import "remoting/client/ios/key_input.h"
 
 typedef NS_ENUM(NSInteger, HostInputScheme) {
@@ -42,10 +43,14 @@ typedef NS_ENUM(NSInteger, MouseButton) {
   UIScreenEdgePanGestureRecognizer* _edgeGesture;
   UISwipeGestureRecognizer* _swipeGesture;
 
+  __weak UIView* _view;
+  remoting::DesktopViewport* _viewport;
+
   HostInputScheme _inputScheme;
 }
 
-- (instancetype)initWithView:(UIView*)view;
+- (instancetype)initWithView:(UIView*)view
+                    viewport:(remoting::DesktopViewport*)vp;
 
 // Zoom in/out
 - (IBAction)pinchGestureTriggered:(UIPinchGestureRecognizer*)sender;