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

ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h

Index: ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h
diff --git a/ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h b/ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h
index 6dba94faea42df1e58662ba186dd84de29003476..849c3313ac52a000b062f3ee3ec5a99a557fcfef 100644
--- a/ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h
+++ b/ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h
@@ -142,12 +142,12 @@ typedef enum {
 
 // Redeclare the delegate property to be the more specific
 // OmniboxTextFieldDelegate.
-@property(nonatomic, assign) id<OmniboxTextFieldDelegate> delegate;
+@property(nonatomic, weak) id<OmniboxTextFieldDelegate> delegate;
 
-@property(nonatomic, retain) NSString* preEditText;
+@property(nonatomic, strong) NSString* preEditText;
 @property(nonatomic) BOOL clearingPreEditText;
-@property(nonatomic, retain) UIColor* selectedTextBackgroundColor;
-@property(nonatomic, retain) UIColor* placeholderTextColor;
+@property(nonatomic, strong) UIColor* selectedTextBackgroundColor;
+@property(nonatomic, strong) UIColor* placeholderTextColor;
 @property(nonatomic, assign) BOOL incognito;
 
 @end