[iOS] Stop swizzling the |init| method of CameraController.

ios/chrome/browser/ui/qr_scanner/camera_controller.mm

Index: ios/chrome/browser/ui/qr_scanner/camera_controller.mm
diff --git a/ios/chrome/browser/ui/qr_scanner/camera_controller.mm b/ios/chrome/browser/ui/qr_scanner/camera_controller.mm
index b4fded5911d07d93f9da8e90dddecf93d1ba29d2..e5ecb321f7a610049114742b4b942920d683406f 100644
--- a/ios/chrome/browser/ui/qr_scanner/camera_controller.mm
+++ b/ios/chrome/browser/ui/qr_scanner/camera_controller.mm
@@ -34,6 +34,10 @@ @interface CameraController ()<AVCaptureMetadataOutputObjectsDelegate> {
 @property(nonatomic, readwrite, assign, getter=isTorchAvailable)
     BOOL torchAvailable;
 
+// Initializes the controller with the |delegate|.
+- (instancetype)initWithDelegate:(id<CameraControllerDelegate>)delegate
+    NS_DESIGNATED_INITIALIZER;
+
 // YES if |cameraState| is CAMERA_AVAILABLE.
 - (BOOL)isCameraAvailable;
 // Starts receiving notfications about changes to the capture session and to the
@@ -58,6 +62,13 @@ @implementation CameraController {
 
 #pragma mark lifecycle
 
++ (instancetype)cameraControllerWithDelegate:
+    (id<CameraControllerDelegate>)delegate {
+  CameraController* cameraController =
+      [[CameraController alloc] initWithDelegate:delegate];
+  return cameraController;
+}
+
 - (instancetype)initWithDelegate:(id<CameraControllerDelegate>)delegate {
   self = [super init];
   if (self) {