WindowInsets: populate system gesture and tappable element insets

Also fixes an infinite recursion when invoking
TestableContext.(un)registerComponentCallbacks().

Test: atest WindowInsetsPolicyTest
Bug: 126511573
Change-Id: I5c9f40054493a83746bce6124d72412e8eb8a0d1
diff --git a/packages/overlays/NavigationBarModeGesturalOverlay/res/values/config.xml b/packages/overlays/NavigationBarModeGesturalOverlay/res/values/config.xml
index 545a3cc..23d2e7b 100644
--- a/packages/overlays/NavigationBarModeGesturalOverlay/res/values/config.xml
+++ b/packages/overlays/NavigationBarModeGesturalOverlay/res/values/config.xml
@@ -26,4 +26,11 @@
     <!-- Controls whether the nav bar can move from the bottom to the side in landscape.
          Only applies if the device display is not square. -->
     <bool name="config_navBarCanMove">false</bool>
-</resources>
\ No newline at end of file
+
+    <!-- Controls whether the navigation bar lets through taps. -->
+    <bool name="config_navBarTapThrough">true</bool>
+
+    <!-- Controls the size of the back gesture inset. -->
+    <dimen name="config_backGestureInset">48dp</dimen>
+
+</resources>