Adding mediator for Sign-in promo

ios/chrome/browser/ui/authentication/signin_promo_view.h

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef IOS_CHROME_BROWSER_UI_AUTHENTICATION_SIGN_PROMO_VIEW_H_
+#define IOS_CHROME_BROWSER_UI_AUTHENTICATION_SIGN_PROMO_VIEW_H_

[lpromero, 2017/03/24 10:36:20]

Since this view has quite some logic, can you add tests?

[jlebel, 2017/03/24 20:59:08]

Done.

+
+#import <UIKit/UIKit.h>
+
+@class MDCFlatButton;
+@class SigninPromoView;
+
+// Configures a SigninPromoView view.
+@protocol SigninPromoViewConfigurator<NSObject>
+
+- (void)configureSigninPromoView:(SigninPromoView*)signinPromoView;
+
+@end
+
+typedef NS_ENUM(NSInteger, SigninPromoViewMode) {
+  // No profile is known.
+  SigninPromoViewColdStartMode,
+  // At least one profile is known and the user can sign without entering their
+  // password.
+  SigninPromoViewWarmStartMode,

[msarda, 2017/03/22 12:18:38]

I think the only difference between warm and cold modes are the fact that the
secondaryButton is hidden (see my comment concerning the image below).
If so, then please rename these to:
* SigninPromoHideSecondaryButton
* SigninPromoShowSecondaryButton

Another more simple option would be to add a method
setSecondaryButtonHidden:(BOOL)hidden that hides or shows the secondary button.

[jlebel, 2017/03/24 20:59:08]

Since I would like to keep the chrome icon inside the view, the mode is more
than just showing/hiding the secondary button. I suggest to rename it to
SigninPromoViewColdStateMode/SigninPromoViewWarmStateMode.
Does it ok with you?

+};
+
+// This class creates an image view, a label and 2 buttons. This view can be
+// configured with 2 modes : "Cold Start" and "Warm Start".
+// + "Cold Start" mode displays the chrome/chomium icon in the image view, and

[msarda, 2017/03/22 12:18:39]

I think the imageView should be configured by the mediator, so it is unnecessary
to specify it here. Basically, this class displays the image that is passed to
it.

[jlebel, 2017/03/24 20:59:08]

As Louis mention it, it is nicer to keep it in the view.

+//    only displays the primary button.
+// + "Warm Start" mode displays the image view (big than the cold start mode),
+//   displays both buttons.
+//
+// The owner is in charge to set:
+//   - the image for |imageView|, using -[SigninPromoView setProfileImage:]

[msarda, 2017/03/22 12:18:38]

I think the mediator should always set the image this view should display.

[jlebel, 2017/03/24 20:59:08]

Acknowledged.

+//     (only for "Warm Start")
+//   - the label for |textLabel|
+//   - the title for |primaryButton|
+//   - the title for |secondaryButton|
+@interface SigninPromoView : UIView
+
+@property(nonatomic) SigninPromoViewMode mode;
+@property(nonatomic, readonly) UIImageView* imageView;
+@property(nonatomic, readonly) UILabel* textLabel;
+@property(nonatomic, readonly) MDCFlatButton* primaryButton;
+@property(nonatomic, readonly) MDCFlatButton* secondaryButton;
+
+// Horizontal padding used for |textLabel|, |primaryButton| and
+// |secondaryButton|. Used to compute the preferred max layout of the text
+// label.

[msarda, 2017/03/22 12:18:38]

s/of the text label./of |textLabel|

[jlebel, 2017/03/24 20:59:08]

Done.

+@property(nonatomic, readonly) CGFloat horizontalPadding;
+
+- (instancetype)initWithCoder:(NSCoder*)aDecoder NS_UNAVAILABLE;
+
+// Changes the image in |imageView| with a circular image. Should be called

[lpromero, 2017/03/24 10:36:19]

Can you be more explicit with the "circular"? The image that is passed can be
whatever, but this method will make it circular.

[jlebel, 2017/03/24 20:59:08]

Done.

+// only with the "Warm Start" mode. The image is not changed when "Cold Start"
+// mode.
+- (void)setProfileImage:(UIImage*)image;

[msarda, 2017/03/22 12:18:39]

I think the owner should always set the image (not only for the profileImage
case).

[lpromero, 2017/03/24 10:36:20]

The Chrome logo can stay inside this class, to me. (BTW< did you check that the
asset is branded? i.e. Blue for Chromium, colored for Chrome?)

[jlebel, 2017/03/24 20:59:08]

Yes, I have the asset with all colors. I will add them in another patch.

+
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_AUTHENTICATION_SIGN_PROMO_VIEW_H_