Add template types to Multimap. Although the presence of a 'K' type implies that the Multimap can accept any kind of keys, in fact the keys must be strings (although we are working towards fixing that).
Add template types to Multimap. Although the presence of a 'K' type implies that the Multimap can accept any kind of keys, in fact the keys must be strings (although we are working towards fixing that).

RELNOTES: none

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=179502956

teppeis/closure-library,teppeis/closure-library,google/closure-library,google/closure-library,teppeis/closure-library,teppeis/closure-library,google/closure-library,google/closure-library,lucidsoftware/closure-library,google/closure-library,lucidsoftware/closure-library,lucidsoftware/closure-library,lucidsoftware/closure-library