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

ios/chrome/browser/ui/omnibox_perftest.mm

Index: ios/chrome/browser/ui/omnibox_perftest.mm
diff --git a/ios/chrome/browser/ui/omnibox_perftest.mm b/ios/chrome/browser/ui/omnibox_perftest.mm
index cff7b6c6e54703bf729b30d4cb55353ca350c2cf..1c10b646a74ec00a377ac883117d29d80ffe74b1 100644
--- a/ios/chrome/browser/ui/omnibox_perftest.mm
+++ b/ios/chrome/browser/ui/omnibox_perftest.mm
@@ -6,7 +6,6 @@
 
 #include <memory>
 
-#include "base/mac/scoped_nsobject.h"
 #include "base/memory/ptr_util.h"
 #import "base/test/ios/wait_util.h"
 #include "base/time/time.h"
@@ -26,6 +25,10 @@
 #import "third_party/ocmock/OCMock/OCMock.h"
 #import "ui/base/test/ios/keyboard_appearance_listener.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 // Descends down a view hierarchy until the first view of |specificClass|
@@ -65,11 +68,11 @@ class OmniboxPerfTest : public PerfTest {
         chrome_browser_state_.get());
 
     // Sets up the listener for keyboard activation/deactivation notifications.
-    keyboard_listener_.reset([[KeyboardAppearanceListener alloc] init]);
+    keyboard_listener_ = [[KeyboardAppearanceListener alloc] init];
 
     // Create a real window to host the Toolbar.
     CGRect screenBounds = [[UIScreen mainScreen] bounds];
-    window_.reset([[UIWindow alloc] initWithFrame:screenBounds]);
+    window_ = [[UIWindow alloc] initWithFrame:screenBounds];
     [window_ makeKeyAndVisible];
 
     // Create a WebStateList that will always return the test WebState as
@@ -93,11 +96,11 @@ class OmniboxPerfTest : public PerfTest {
     [[[webToolbarDelegate stub] andReturnValue:OCMOCK_VALUE(model_for_mock)]
         toolbarModelIOS];
     id urlLoader = [OCMockObject niceMockForProtocol:@protocol(UrlLoader)];
-    toolbar_.reset([[WebToolbarController alloc]
+    toolbar_ = [[WebToolbarController alloc]
         initWithDelegate:webToolbarDelegate
                urlLoader:urlLoader
             browserState:chrome_browser_state_.get()
-         preloadProvider:nil]);
+         preloadProvider:nil];
     UIView* toolbarView = [toolbar_ view];
     CGRect toolbarFrame = toolbarView.frame;
     toolbarFrame.origin = CGPointZero;
@@ -106,7 +109,7 @@ class OmniboxPerfTest : public PerfTest {
     // Add toolbar to window.
     [window_ addSubview:toolbarView];
     base::test::ios::WaitUntilCondition(^bool() {
-      return IsToolbarLoaded(window_.get());
+      return IsToolbarLoaded(window_);
     });
   }
 
@@ -114,7 +117,7 @@ class OmniboxPerfTest : public PerfTest {
     // Remove toolbar from window.
     [[toolbar_ view] removeFromSuperview];
     base::test::ios::WaitUntilCondition(^bool() {
-      return !IsToolbarLoaded(window_.get());
+      return !IsToolbarLoaded(window_);
     });
     [toolbar_ browserStateDestroyed];
     PerfTest::TearDown();
@@ -148,8 +151,8 @@ class OmniboxPerfTest : public PerfTest {
   // Omnibox focus timings. Call this function to preload keyboard before
   // doing the real test.
   base::TimeDelta PreLoadKeyboard() {
-    base::scoped_nsobject<UITextField> textField(
-        [[UITextField alloc] initWithFrame:CGRectMake(20, 100, 280, 29)]);
+    UITextField* textField =
+        [[UITextField alloc] initWithFrame:CGRectMake(20, 100, 280, 29)];
     [textField setBorderStyle:UITextBorderStyleRoundedRect];
     [window_ addSubview:textField];
     base::TimeDelta elapsed = base::test::ios::TimeUntilCondition(
@@ -205,9 +208,9 @@ class OmniboxPerfTest : public PerfTest {
   std::unique_ptr<WebStateList> web_state_list_;
   std::unique_ptr<ToolbarModelDelegateIOS> toolbar_model_delegate_;
   std::unique_ptr<ToolbarModelIOS> toolbar_model_ios_;
-  base::scoped_nsobject<WebToolbarController> toolbar_;
-  base::scoped_nsobject<UIWindow> window_;
-  base::scoped_nsobject<KeyboardAppearanceListener> keyboard_listener_;
+  WebToolbarController* toolbar_;
+  UIWindow* window_;
+  KeyboardAppearanceListener* keyboard_listener_;
 };
 
 // Measures the amount of time it takes the Omnibox text field to activate