fix(ios): redraw when the view re-enters a window

packages/skia/apple/MetalWindowContext.mm

@@ -89,7 +89,16 @@
   }
 
   id<MTLCommandBuffer> commandBuffer([_commandQueue commandBuffer]);
-  [commandBuffer presentDrawable:_currentDrawable];
-  [commandBuffer commit];
+  if (_layer.presentsWithTransaction) {
+    // Present inside the current Core Animation transaction: commit, wait
+    // until the command buffer is scheduled, then present the drawable
+    // directly (CAMetalLayer.presentsWithTransaction documentation).
+    [commandBuffer commit];
+    [commandBuffer waitUntilScheduled];
+    [_currentDrawable present];
+  } else {
+    [commandBuffer presentDrawable:_currentDrawable];
+    [commandBuffer commit];
+  }
   _skSurface = nullptr;
 }

packages/skia/apple/SkiaUIView.mm

@@ -138,6 +138,24 @@ - (void)drawRect:(CGRect)rect {
   }
 }
 
+#if !TARGET_OS_OSX
+- (void)didMoveToWindow {
+  [super didMoveToWindow];
+  // A frame drawn while the view was detached from the window (an inactive
+  // tab, a covered screen) is never presented, so redraw the current picture
+  // as soon as the view is back in a window instead of showing the last
+  // frame that was presented before it left. Present it inside the current
+  // Core Animation transaction so it is on screen in the same frame the view
+  // appears rather than one later.
+  if (self.window != nil && _impl != nullptr) {
+    CAMetalLayer *layer = (CAMetalLayer *)_impl->getLayer();
+    layer.presentsWithTransaction = YES;
+    _impl->getDrawView()->redraw();
+    layer.presentsWithTransaction = NO;
+  }
+}
+#endif // !TARGET_OS_OSX
+
 #pragma mark Layout
 
 - (void)layoutSubviews {