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

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

Index: ios/chrome/browser/ui/toolbar/toolbar_tools_menu_button.mm
diff --git a/ios/chrome/browser/ui/toolbar/toolbar_tools_menu_button.mm b/ios/chrome/browser/ui/toolbar/toolbar_tools_menu_button.mm
index dff031ab80643357197193bb048d398b746cf5e2..12fbf0860e9bb12ca050e703d46c6bed7a0d2424 100644
--- a/ios/chrome/browser/ui/toolbar/toolbar_tools_menu_button.mm
+++ b/ios/chrome/browser/ui/toolbar/toolbar_tools_menu_button.mm
@@ -9,6 +9,10 @@
 
 #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;
@@ -48,7 +52,7 @@ const CGFloat kLineWidthAtApogee = 3;
   // Whether the reading list contains unseen items.
   BOOL readingListContainsUnseenItems_;
   // The CALayers containing the drawn dots.
-  base::scoped_nsobject<CAShapeLayer> pathLayers_[kNumberOfDots];
+  NSMutableArray<CAShapeLayer*>* pathLayers_;
   // Whether the CALayers are being animated.
   BOOL animationOnGoing_;
 }
@@ -76,6 +80,7 @@ const CGFloat kLineWidthAtApogee = 3;
                         style:(ToolbarControllerStyle)style {
   if (self = [super initWithFrame:frame]) {
     style_ = style;
+    pathLayers_ = [[NSMutableArray alloc] initWithCapacity:kNumberOfDots];
 
     [self setTintColor:toolbar::NormalButtonTint(style_)
               forState:UIControlStateNormal];
@@ -112,10 +117,9 @@ const CGFloat kLineWidthAtApogee = 3;
 }
 
 - (void)initializeShapeLayers {
-  for (int i = 0; i < kNumberOfDots; i++) {
-    base::scoped_nsobject<CAShapeLayer>& pathLayer = pathLayers_[i];
-    if (pathLayer) {
-      [pathLayer removeFromSuperlayer];
+  for (NSUInteger i = 0; i < kNumberOfDots; i++) {
+    if (i < pathLayers_.count) {
+      [pathLayers_[i] removeFromSuperlayer];
     }
 
     const CGFloat x = kDotOffsetX;
@@ -125,7 +129,7 @@ const CGFloat kLineWidthAtApogee = 3;
     [path moveToPoint:CGPointMake(x - kMaxWidthOfSegment * 0.5, y)];
     [path addLineToPoint:CGPointMake(x + kMaxWidthOfSegment * 0.5, y)];
 
-    pathLayer.reset([[CAShapeLayer layer] retain]);
+    CAShapeLayer* pathLayer = [CAShapeLayer layer];
     [pathLayer setFrame:self.bounds];
     [pathLayer setPath:path.CGPath];
     [pathLayer setStrokeColor:[self.tintColor CGColor]];
@@ -134,7 +138,8 @@ const CGFloat kLineWidthAtApogee = 3;
     [pathLayer setLineCap:kCALineCapRound];
     [pathLayer setStrokeStart:kStrokeStartAtRest];
     [pathLayer setStrokeEnd:kStrokeEndAtRest];
-    [self.layer addSublayer:pathLayer.get()];
+    [self.layer addSublayer:pathLayer];
+    pathLayers_[i] = pathLayer;

[sdefresne, 2017/05/02 14:19:28]

I don't think you can set objects past the NSArray "count".

If I read the documentation of NSMutableArray correctly [1], "pathLayers_[i] =
pathLayer;" is translated to "[pathLayers_ placeObjectAtIndex:i
withObject:pathLayer];". The method documentation [2], states that "The index of
the object to be replaced. This value must not exceed the bounds of the array.".

[1]: https://developer.apple.com/reference/foundation/nsmutablearray
[2]:
https://developer.apple.com/reference/foundation/nsmutablearray/1414510-repla...

If think this method should be slightly changed to work with an NSMutableArray.
I would recommend iterating twice, first time to call -removeFromSuperlayer on
all objects, then adding all new values. Something like this:

- (void)initializeShapeLayers {
  for (NSUInteger index = 0; index < pathLayers_.count; ++index) {
    [pathLayers_[index] removeFromSuperlayer];
  }
  pathLayers_ = [[NSMutableArray alloc] initWithCapacity:kNumberOfDots];
  for (NSUInteger index = 0; index < kNumberOfDots; ++index) {
    ...
    [pathLayers_ addObject:pathLayer];
  }
}

[gambard, 2017/05/02 15:19:02]

It seemed to work but it makes more sense to do it this way.

   }
 }
 
@@ -204,10 +209,10 @@ const CGFloat kLineWidthAtApogee = 3;
 - (void)animateToColor:(UIColor*)targetColor {
   animationOnGoing_ = YES;
 
+  DCHECK(pathLayers_.count == kNumberOfDots);
   // 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];
     const int frameStart =
         (kNumberOfDots - i) * kFramesBetweenAnimationOfEachDot;