am dd7d95bd: Merge "GC step 4. Update all positions in new dict and add a test."

...cyimpl/dictionary/bigram/bigram_list_read_write_utils.cpp

...licyimpl/dictionary/bigram/dynamic_bigram_list_policy.cpp

...policyimpl/dictionary/bigram/dynamic_bigram_list_policy.h

...l/dictionary/dynamic_patricia_trie_gc_event_listeners.cpp

...mpl/dictionary/dynamic_patricia_trie_gc_event_listeners.h

...st/policyimpl/dictionary/dynamic_patricia_trie_policy.cpp

...yimpl/dictionary/dynamic_patricia_trie_reading_helper.cpp

...yimpl/dictionary/dynamic_patricia_trie_writing_helper.cpp

...icyimpl/dictionary/dynamic_patricia_trie_writing_helper.h

...licyimpl/dictionary/dynamic_patricia_trie_writing_utils.h

.../com/android/inputmethod/latin/BinaryDictionaryTests.java