Isolate the IServiceCallback registration behind its own class - #926
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ART resolves the superclass of every type a method mentions when it verifies that method, not when the branch mentioning it runs. The `Build.VERSION.SDK_INT >= R` gate therefore never got a chance to help: verifying registerProxyService resolved the anonymous callback, that resolved `android.os.IServiceCallback$Stub`, and on Android 9 the daemon logged a NoClassDefFoundError for its very first call even though the guarded code was never executed. Move the callback into a holder object that the gate only touches on R and newer, so the resolution is deferred to its class initialization, and pin the holder in the R8 rules so a release build cannot inline it back into the caller and reintroduce the reference. Fixes #925
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On Android 9 the daemon logs a
NoClassDefFoundErrorforandroid.os.IServiceCallback$Stubbefore it prints anything of its own. The reported stack tops out atVectorDaemon.mainwithClassLoader.loadClassframes, which is the giveaway: this is ART resolving classes while it verifiesregisterProxyService, not while it runs it.IServiceCallbackonly exists since Android R, and the callback was written as an anonymousobject : IServiceCallback.Stub()inside theSDK_INT >= Rbranch. That gate could never work — ART resolves every type a method mentions at verification time, and loading that type resolves its superclass, so the reference alone was enough.