Fixes Objective-C objects memory leaks

shell/platform/darwin/ios/framework/Source/FlutterPlatformViews.mm

@@ -253,7 +253,7 @@
   // If there were not enough existing clip views, add more.
   while (clipIndex < number_of_clips) {
     ChildClippingView* clippingView =
-        [[ChildClippingView alloc] initWithFrame:flutter_view_.get().bounds];
+        [[[ChildClippingView alloc] initWithFrame:flutter_view_.get().bounds] autorelease];
     [clippingView addSubview:head];
     head = clippingView;
     clipIndex++;
@@ -467,8 +467,7 @@
     if (overlays_.count(overlay_id) != 0) {
       return;
     }
-    fml::scoped_nsobject<FlutterOverlayView> overlay_view(
-        [[[FlutterOverlayView alloc] init] retain]);
+    fml::scoped_nsobject<FlutterOverlayView> overlay_view([[FlutterOverlayView alloc] init]);
     overlay_view.get().frame = flutter_view_.get().bounds;
     overlay_view.get().autoresizingMask =
         (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight);
@@ -493,7 +492,7 @@
   }
   auto contentsScale = flutter_view_.get().layer.contentsScale;
   fml::scoped_nsobject<FlutterOverlayView> overlay_view(
-      [[[FlutterOverlayView alloc] initWithContentsScale:contentsScale] retain]);
+      [[FlutterOverlayView alloc] initWithContentsScale:contentsScale]);
   overlay_view.get().frame = flutter_view_.get().bounds;
   overlay_view.get().autoresizingMask =
       (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight);

shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.mm

@@ -56,9 +56,9 @@ + (CGRect)getCGRectFromSkRect:(const SkRect&)clipSkRect {
 - (void)clipRect:(const SkRect&)clipSkRect {
   CGRect clipRect = [ChildClippingView getCGRectFromSkRect:clipSkRect];
   CGPathRef pathRef = CGPathCreateWithRect(clipRect, nil);
-  CAShapeLayer* clip = [[CAShapeLayer alloc] init];
-  clip.path = pathRef;
-  self.layer.mask = clip;
+  fml::scoped_nsobject<CAShapeLayer> clip([[CAShapeLayer alloc] init]);
+  clip.get().path = pathRef;
+  self.layer.mask = clip.get();
   CGPathRelease(pathRef);
 }
 
@@ -125,9 +125,9 @@ - (void)clipRRect:(const SkRRect&)clipSkRRect {
   // TODO(cyanglaz): iOS does not seem to support hard edge on CAShapeLayer. It clearly stated that
   // the CAShaperLayer will be drawn antialiased. Need to figure out a way to do the hard edge
   // clipping on iOS.
-  CAShapeLayer* clip = [[CAShapeLayer alloc] init];
-  clip.path = pathRef;
-  self.layer.mask = clip;
+  fml::scoped_nsobject<CAShapeLayer> clip([[CAShapeLayer alloc] init]);
+  clip.get().path = pathRef;
+  self.layer.mask = clip.get();
   CGPathRelease(pathRef);
 }
 
@@ -137,9 +137,9 @@ - (void)clipPath:(const SkPath&)path {
     return;
   }
   if (path.isEmpty()) {
-    CAShapeLayer* clip = [[CAShapeLayer alloc] init];
-    clip.path = pathRef;
-    self.layer.mask = clip;
+    fml::scoped_nsobject<CAShapeLayer> clip([[CAShapeLayer alloc] init]);
+    clip.get().path = pathRef;
+    self.layer.mask = clip.get();
     CGPathRelease(pathRef);
     return;
   }
@@ -195,9 +195,9 @@ - (void)clipPath:(const SkPath&)path {
     verb = iter.next(pts);
   }
 
-  CAShapeLayer* clip = [[CAShapeLayer alloc] init];
-  clip.path = pathRef;
-  self.layer.mask = clip;
+  fml::scoped_nsobject<CAShapeLayer> clip([[CAShapeLayer alloc] init]);
+  clip.get().path = pathRef;
+  self.layer.mask = clip.get();
   CGPathRelease(pathRef);
 }