An Android test was occasionally crashing with a SEGV in ConsumeDecimalNumber
Switching a local variable from an int to uint64_t eliminated these crashes.
Speculating this is either a compiler, runtime library, or emulator issue.

Switching this type to uint64_t also eliminates a compiler warning
about comparing an int with a uint64_t.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=166399695