Rename upload_gtest_test_results.py to upload_test_results.py.

The motivation is to reuse the logic of uploading test results to support other
format such as JSON Test Result format.

*This CL was split from https://crrev.com/2410613002

BUG=649762

Review-Url: https://codereview.chromium.org/2411763002
133 files changed