Add test for ProtoLog calls before initialization.

Verifies that calling ProtoLog logging methods before `ProtoLog.init()`
does not throw an exception, confirming the intended behavior of
preventing crashes in this scenario.



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Original Change: ag/35157468
Test: ATP tests passed http://go/forrest-run/L95900030017377343
Bug: 431235865
Flag: TEST_ONLY

Change-Id: Id21a303caf98cc8d2181d4b5fc3a8e712a88d315