[CDM][CMD] Check permissions for CDM shell commands Override handleShellCommand instead of onShellCommand because Binder.onShellCommand checks the necessary permissions of the caller. Bug: 313428840 Test: manually tested CDM shell commands (cherry picked from commit 1761a0fee9c2cd9787bbb7fbdbe30b4c2b03396e) (cherry picked from https://googleplex-android-review.googlesource.com/q/commit:8d008c61451dba86aa9f14c6bcd661db2cea4856) Merged-In: I5539b3594feb5544c458c0fd1061b51a0a808900 Change-Id: I5539b3594feb5544c458c0fd1061b51a0a808900