Fix crash when using the language picker on iOS

The crash was happening because the wrong constructor of scoped_nsobject,
because the template parameter did not exactly match the declaration.
The automatic conversion to pointer was used, and the crash happened
because the object was not retained.
With the new code, the copy constructor is used instead, as was intended.

Review URL: https://codereview.chromium.org/793463004

Cr-Commit-Position: refs/heads/master@{#311446}

ios/chrome/browser/translate/before_translate_infobar_controller.mm

@@ -216,15 +216,15 @@ NSTimeInterval kPickerAnimationDurationInSeconds = 0.2;
       languagePickerFrame.size.height + navigationBarFrame.size.height;
   languagePickerFrame.origin.y += animationHeight;
   navigationBarFrame.origin.y += animationHeight;
-  base::scoped_nsobject<UIView> blockLanguagePicker(_languagePicker);
-  base::scoped_nsobject<UIView> blockNavigationBar(_navigationBar);
+  auto blockLanguagePicker(_languagePicker);
+  auto blockNavigationBar(_navigationBar);
   _languagePicker.reset();
   _navigationBar.reset();
   void (^animations)(void) = ^{
     blockLanguagePicker.get().frame = languagePickerFrame;
     blockNavigationBar.get().frame = navigationBarFrame;
   };
-  base::scoped_nsobject<UIView> blockSelectionView(_languageSelectionView);
+  auto blockSelectionView(_languageSelectionView);
   _languageSelectionView.reset();
   void (^completion)(BOOL finished) = ^(BOOL finished) {
     [blockSelectionView removeFromSuperview];
@@ -336,8 +336,8 @@ NSTimeInterval kPickerAnimationDurationInSeconds = 0.2;
   [_languagePicker setBackgroundColor:[infoBarView_ backgroundColor]];
   [_languagePicker selectRow:selectedRow inComponent:0 animated:NO];
 
-  base::scoped_nsobject<UIView> blockLanguagePicker(_languagePicker);
-  base::scoped_nsobject<UIView> blockNavigationBar(_navigationBar);
+  auto blockLanguagePicker(_languagePicker);
+  auto blockNavigationBar(_navigationBar);
   [UIView animateWithDuration:kPickerAnimationDurationInSeconds
                    animations:^{
                      blockLanguagePicker.get().frame = finalPickerFrame;