Fix RetryableMountingLayerException crash in SurfaceMountingManager.addViewAt#56654
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Fix RetryableMountingLayerException crash in SurfaceMountingManager.addViewAt#56654Improbability42 wants to merge 1 commit intofacebook:mainfrom
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…ddViewAt Summary: ## Problem The `addViewAt` method in `SurfaceMountingManager` crashes with a `RetryableMountingLayerException` when trying to find a `ViewState` for a child tag that doesn't exist in the `tagToViewState` map. **Error:** `Unable to find viewState for tag 290. Surface stopped: false` **Logview:** [252c85116a7ab5c4ec93ef3c3373cf9d](https://www.internalfb.com/logview/system_vros_crashes/252c85116a7ab5c4ec93ef3c3373cf9d) ## Root Cause The `addViewAt` method uses `getViewState()` which throws `RetryableMountingLayerException` when a tag is not found. This can happen due to race conditions where a view's state is removed (e.g., during surface cleanup or view deletion) before the mount item that references it is executed. ## Fix Replaced `getViewState()` calls with `getNullableViewState()` + null checks + soft exception logging + early return for both the parent and child tag lookups in `addViewAt`. This matches the existing pattern already used by `removeViewAt`, which handles the same scenario gracefully. The fix: - Uses `getNullableViewState(parentTag)` instead of `getViewState(parentTag)` for the parent view state lookup - Uses `getNullableViewState(tag)` instead of `getViewState(tag)` for the child view state lookup - Adds null check for the child view itself - Logs soft exceptions with the `SURFACE_MOUNTING_MANAGER_MISSING_VIEWSTATE` category for monitoring - Returns early instead of crashing, allowing the surface to continue operating Changelog: [Android][Fixed] - Fixed crash in SurfaceMountingManager.addViewAt when viewState is missing for a tag Differential Revision: D99364621
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Summary:
Problem
The
addViewAtmethod inSurfaceMountingManagercrashes with aRetryableMountingLayerExceptionwhen trying to find aViewStatefor a child tag that doesn't exist in thetagToViewStatemap.Error:
Unable to find viewState for tag 290. Surface stopped: falseLogview: 252c85116a7ab5c4ec93ef3c3373cf9d
Root Cause
The
addViewAtmethod usesgetViewState()which throwsRetryableMountingLayerExceptionwhen a tag is not found. This can happen due to race conditions where a view's state is removed (e.g., during surface cleanup or view deletion) before the mount item that references it is executed.Fix
Replaced
getViewState()calls withgetNullableViewState()+ null checks + soft exception logging + early return for both the parent and child tag lookups inaddViewAt. This matches the existing pattern already used byremoveViewAt, which handles the same scenario gracefully.The fix:
getNullableViewState(parentTag)instead ofgetViewState(parentTag)for the parent view state lookupgetNullableViewState(tag)instead ofgetViewState(tag)for the child view state lookupSURFACE_MOUNTING_MANAGER_MISSING_VIEWSTATEcategory for monitoringChangelog: [Android][Fixed] - Fixed crash in SurfaceMountingManager.addViewAt when viewState is missing for a tag
Differential Revision: D99364621