[ObjC ARC] Converts ios/chrome/browser/passwords:passwords to ARC.

ios/chrome/browser/passwords/password_generation_edit_view.mm

Index: ios/chrome/browser/passwords/password_generation_edit_view.mm
diff --git a/ios/chrome/browser/passwords/password_generation_edit_view.mm b/ios/chrome/browser/passwords/password_generation_edit_view.mm
index 9632ea7dfe001cb4a0e78be829493355f36e79ae..26e7d13d757df9802d82eb146d9b0a0f8c8d86be 100644
--- a/ios/chrome/browser/passwords/password_generation_edit_view.mm
+++ b/ios/chrome/browser/passwords/password_generation_edit_view.mm
@@ -6,16 +6,19 @@
 
 #include "base/i18n/rtl.h"
 #include "base/logging.h"
-#include "base/mac/scoped_nsobject.h"
 #include "ios/chrome/browser/passwords/password_generation_utils.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 // Constants for the edit view.
 const CGFloat kEditViewFontSize = 15;
 }  // namespace
 
 @implementation PasswordGenerationEditView {
-  base::scoped_nsobject<UITextField> _textField;
+  UITextField* _textField;
 }
 
 - (instancetype)initWithPassword:(NSString*)password {
@@ -23,7 +26,7 @@ const CGFloat kEditViewFontSize = 15;
   const CGRect defaultFrameSize = CGRectMake(0, 0, 100, 30);
   self = [super initWithFrame:defaultFrameSize];
   if (self) {
-    _textField.reset([[UITextField alloc] init]);
+    _textField = [[UITextField alloc] init];
     [_textField setText:password];
     [_textField setFont:[UIFont systemFontOfSize:kEditViewFontSize]];
     [_textField setBackgroundColor:[UIColor clearColor]];