Add python-google.gni and valgrind.gni to list all files under tools/python/google and tools/valgrind respectively.

This will be used to include them as run-time dependencies when the tests are run with memcheck on swarming.

BUG=chromium:497757

Review-Url: https://codereview.chromium.org/2517953007
Cr-Commit-Position: refs/heads/master@{#434250}
2 files changed