app: set timezone on app initialization
app: set timezone on app initialization

This trusts bionic's reading of the system clock.

Future work should address the fact we cannot read the Android
zoneinfo file.

Fixes golang/go#10857.

Change-Id: I5a684fecc920dce5ab8f624658e91d9e2d71738d
Reviewed-on: https://go-review.googlesource.com/10299
Reviewed-by: Elias Naur <993af7099cb24ce1a88d64108ae1e8b0385f2fc0@gmail.com>
Reviewed-by: Hyang-Ah Hana Kim <d7e82c3c07f92613bcbf9a1e88f6b96c13caa3b0@gmail.com>

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