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

ios/chrome/browser/ui/toolbar/toolbar_tools_menu_button.mm

 // Copyright 2016 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.
 
 #import "ios/chrome/browser/ui/toolbar/toolbar_tools_menu_button.h"
 
 #import <QuartzCore/CAAnimation.h>
 #import <QuartzCore/CAMediaTimingFunction.h>
 
 #include "ios/chrome/browser/ui/toolbar/toolbar_button_tints.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 // The number of dots drawn.
 const int kNumberOfDots = 3;
 // Position of the topmost dot.
 const CGFloat kDotOffsetX = 22;
 const CGFloat kDotOffsetY = 18;
 // Vertical space between dots.
 const CGFloat kVerticalSpaceBetweenDots = 6;
 // The duration of the animation, in seconds.
 const CFTimeInterval kAnimationDuration = 1;
@@ skipping 19 matching lines @@
 }  // namespace
 
 @interface ToolbarToolsMenuButton ()<CAAnimationDelegate> {
   // The style of the toolbar the button is in.
   ToolbarControllerStyle style_;
   // Whether the tools menu is visible.
   BOOL toolsMenuVisible_;
   // Whether the reading list contains unseen items.
   BOOL readingListContainsUnseenItems_;
   // The CALayers containing the drawn dots.
-  base::scoped_nsobject<CAShapeLayer> pathLayers_[kNumberOfDots];
+  CAShapeLayer* pathLayers_[kNumberOfDots];

[stkhapugin, 2017/04/10 15:57:51]

You should use NSArray of CAShapeLayer and cast to id when you store them, or
CFArray of CAShapeLayer. Your CL is correct in that it takes correct code and
keeps it correct, but it's not a great example of memory management to begin
with, and now it's just odd. 

[sdefresne, 2017/04/10 16:09:45]

If using CFArray, please use base::ScopedCFTypeRef<CFArray> :-)

   // Whether the CALayers are being animated.
   BOOL animationOnGoing_;
 }
 // Updates the tint configuration based on the button's situation, e.g. whether
 // the tools menu is visible or not.
 - (void)updateTintOfButton;
 // Initializes the pathLayers.
 - (void)initializeShapeLayers;
 // Returns a keyframe-based animation of the property identified by |keyPath|.
 // The animation immidiately sets the property's value to |initialValue|.
@@ skipping 44 matching lines @@
     [self setTintColor:toolbar::HighlighButtonTint(style_)
               forState:UIControlStateNormal];
   } else {
     [self setTintColor:toolbar::NormalButtonTint(style_)
               forState:UIControlStateNormal];
   }
 }
 
 - (void)initializeShapeLayers {
   for (int i = 0; i < kNumberOfDots; i++) {
-    base::scoped_nsobject<CAShapeLayer>& pathLayer = pathLayers_[i];
+    CAShapeLayer* pathLayer = pathLayers_[i];
     if (pathLayer) {
       [pathLayer removeFromSuperlayer];
     }
 
     const CGFloat x = kDotOffsetX;
     const CGFloat y = kDotOffsetY + kVerticalSpaceBetweenDots * i;
 
     UIBezierPath* path = [UIBezierPath bezierPath];
     [path moveToPoint:CGPointMake(x - kMaxWidthOfSegment * 0.5, y)];
     [path addLineToPoint:CGPointMake(x + kMaxWidthOfSegment * 0.5, y)];
 
-    pathLayer.reset([[CAShapeLayer layer] retain]);
+    pathLayer = [CAShapeLayer layer];
     [pathLayer setFrame:self.bounds];
     [pathLayer setPath:path.CGPath];
     [pathLayer setStrokeColor:[self.tintColor CGColor]];
     [pathLayer setFillColor:nil];
     [pathLayer setLineWidth:kLineWidthAtRest];
     [pathLayer setLineCap:kCALineCapRound];
     [pathLayer setStrokeStart:kStrokeStartAtRest];
     [pathLayer setStrokeEnd:kStrokeEndAtRest];
-    [self.layer addSublayer:pathLayer.get()];
+    [self.layer addSublayer:pathLayer];
+    pathLayers_[i] = pathLayer;
   }
 }
 
 - (CAAnimation*)animationWithInitialValue:(id)initialValue
                         intermediaryValue:(id)intermediaryValue
                                finalValue:(id)finalValue
                                frameStart:(int)frameStart
                                forKeyPath:(NSString*)keyPath {
   // The property is animated the following way:
   //
@@ skipping 51 matching lines @@
 #endif
 
   return animation;
 }
 
 - (void)animateToColor:(UIColor*)targetColor {
   animationOnGoing_ = YES;
 
   // Add four animations for each stroke.
   for (int i = 0; i < kNumberOfDots; i++) {
-    base::scoped_nsobject<CAShapeLayer>& pathLayer = pathLayers_[i];
-    DCHECK(pathLayer.get());
+    CAShapeLayer* pathLayer = pathLayers_[i];
+    DCHECK(pathLayer);

[stkhapugin, 2017/04/10 15:57:51]

This is an odd DCHECK, but you shouldn't need it with an NSArray.

     const int frameStart =
         (kNumberOfDots - i) * kFramesBetweenAnimationOfEachDot;
 
     // Start of the stroke animation.
     CAAnimation* strokeStartAnimation =
         [self animationWithInitialValue:@(kStrokeStartAtRest)
                       intermediaryValue:@(kStrokeStartAtApogee)
                              finalValue:@(kStrokeStartAtRest)
                              frameStart:frameStart
                              forKeyPath:@"strokeStart"];
@@ skipping 59 matching lines @@
 #pragma mark - CAAnimationDelegate
 
 - (void)animationDidStop:(CAAnimation*)animation finished:(BOOL)flag {
   animationOnGoing_ = NO;
   // Recreate the CAShapeLayers in case the tint code changed while the
   // animation was going on.
   [self initializeShapeLayers];
 }
 
 @end