Fix button padding not being applied correctly on the new arch (#3106)

## Description

Fixes
#3100

Updates the logic for applying the layout metrics, which needs to be
customized due to nested structure of the button on the new architecture
- instead of being just a button view, it's a button view inside a
custom `ViewComponentView`.

Previously all metrics were applied to the wrapper view (including
padding and border insets) which caused the button to be offset in the
wrapper and it's content was offset again (due to children being mounted
under the button instead of the wrapper and their layout metrics
containing frame position).

This PR changes that so that insets are not applied to the wrapper view
at all and the button always fills the container. This way the layout of
the children remains correct.

## Test plan

Tested on the FabricExample app and on the reproducer from the issue.

Author: j-piasecki

apple/RNGestureHandlerButtonComponentView.mm

@@ -50,6 +50,41 @@ - (void)unmountChildComponentView:(UIView<RCTComponentViewProtocol> *)childCompo
   [_buttonView unmountChildComponentView:childComponentView index:index];
 }
 
+- (LayoutMetrics)buildWrapperMetrics:(const LayoutMetrics &)metrics
+{
+  LayoutMetrics result = metrics;
+  result.borderWidth = EdgeInsets::ZERO;
+  result.contentInsets = EdgeInsets::ZERO;
+  return result;
+}
+
+- (LayoutMetrics)buildButtonMetrics:(const LayoutMetrics &)metrics
+{
+  LayoutMetrics result = metrics;
+  result.frame.origin = {0, 0};
+  return result;
+}
+
+- (void)updateLayoutMetrics:(const facebook::react::LayoutMetrics &)layoutMetrics
+           oldLayoutMetrics:(const facebook::react::LayoutMetrics &)oldLayoutMetrics
+{
+  // due to nested structure of Button and ComponentView, layout metrics for both
+  // need to be modified:
+  // - wrapper shouldn't have any insets as they should be applied to the button
+  //   so that it can intercept touches on padding and borders, applying them
+  //   twice breaks expected layout
+  // - frame origin needs to be zeroes on metrics of the button as it should fill
+  //   the entirety of the wrapper component
+  const LayoutMetrics wrapperMetrics = [self buildWrapperMetrics:layoutMetrics];
+  const LayoutMetrics oldWrapperMetrics = [self buildWrapperMetrics:oldLayoutMetrics];
+
+  const LayoutMetrics buttonMetrics = [self buildButtonMetrics:layoutMetrics];
+  const LayoutMetrics oldbuttonMetrics = [self buildButtonMetrics:oldLayoutMetrics];
+
+  [super updateLayoutMetrics:wrapperMetrics oldLayoutMetrics:oldWrapperMetrics];
+  [_buttonView updateLayoutMetrics:buttonMetrics oldLayoutMetrics:oldbuttonMetrics];
+}
+
 #pragma mark - RCTComponentViewProtocol
 
 + (ComponentDescriptorProvider)componentDescriptorProvider