fix: remove NavView fragment via the FragmentManager it is attached to

[christian-apollo]

Fixes #624

Problem

NavViewManager.onDropViewInstance removes the map/navigation fragment through reactContext.getCurrentActivity().getSupportFragmentManager(). The fragment was attached to whichever Activity was current when the fragment transaction was committed. If getCurrentActivity() points at a different Activity at drop time — e.g. after Activity recreation while the original host is still alive — that FragmentManager never hosted the fragment, and androidx throws a fatal:

java.lang.IllegalStateException: Cannot remove Fragment attached to a different FragmentManager.
    at androidx.fragment.app.BackStackRecord.remove(BackStackRecord.java:204)
    at com.google.android.react.navsdk.NavViewManager.onDropViewInstance(NavViewManager.java:317)
    at com.facebook.react.fabric.mounting.SurfaceMountingManager.onViewStateDeleted(SurfaceMountingManager.java:1163)

BackStackRecord.remove throws exactly when fragment.mFragmentManager != null && fragment.mFragmentManager != mManager, i.e. when the transaction's FragmentManager is not the one the fragment is attached to.

Fix

Open the remove transaction on the fragment's own getParentFragmentManager(), which is by definition the FragmentManager the fragment is attached to, so the mismatch can no longer occur. isAdded() is checked first, so getParentFragmentManager() cannot throw for a detached fragment; a remaining IllegalStateException (FragmentManager already destroyed mid-teardown) is caught, since in that case the fragment is torn down with its host Activity anyway.

This also removes the early return when getCurrentActivity() is null — the current Activity is no longer needed for removal, and returning early leaked the fragmentMap entry.

When the current Activity is the fragment's host (the common case), getParentFragmentManager() and activity.getSupportFragmentManager() are the same instance, so behavior is unchanged.

Testing

• We hit this crash in production (Crashlytics, full trace in Android crash on NavView unmount: "Cannot remove Fragment attached to a different FragmentManager" in NavViewManager.onDropViewInstance #624) in com.apolloscooters and have been shipping this exact change via patch-package on top of 0.16.3; the crash signature is eliminated by construction.
• :googlemaps_react-native-navigation-sdk:compileDebugJavaWithJavac passes with the change applied.

🤖 Generated with Claude Code

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