Add benchmarks for LocaleDataLookup

on aosp_cf_x86_64_phone-userdebug, the benchmark result is

libandroidfw_benchmarks#BM_LocaleDataLookupIsLocaleRepresentative: PASSED (0ms)
cpu_time_ns: 55.07607273354898
real_time_ns: 55.19976479889459
libandroidfw_benchmarks#BM_LocaleDataLookupLikelyScript: PASSED (0ms)
cpu_time_ns: 87.99205759931041
real_time_ns: 88.19010674954154

With the unordered_set and unordered_map, the result is

libandroidfw_benchmarks#BM_LocaleDataLookupIsLocaleRepresentative: PASSED (0ms)
cpu_time_ns: 113.01179143336402
real_time_ns: 113.3695957412614
libandroidfw_benchmarks#BM_LocaleDataLookupLikelyScript: PASSED (1ms)
cpu_time_ns: 109.63471229710265
real_time_ns: 109.91545630537807

With std::binary_search, the result is

libandroidfw_benchmarks#BM_LocaleDataLookupIsLocaleRepresentative: PASSED (0ms)
cpu_time_ns: 123.82590108826805
real_time_ns: 123.98891085230711

Let's keep the current implementation, and add a TODO about the disk
size.

Bug: 383096413
Test: atest libandroidfw_benchmarks
Change-Id: Iaa5f1ab5ac4dcc6bbdd3c4b66fe129c61d75c1d1