Cleanup TrialToken in preparation of moving it to content/common.

This includes the following cleanups:

- Pass StringPiece by value rather than const ref, as its documentation
  suggests.
- Represent origins as url::Origin/blink::WebSecurityOrigin.
- Pass feature_name to TrialToken::IsAppropriate and related methods as
  StringPiece. Currently doesn't make a difference yet as TrialTokenValidator
  still converts through std::string, but that can be fixed, and new content
  side code can avoid having to construct strings for feature names this way.
- Store expiry time as base::Time instead of raw int64. Under the hood a
  base::Time is an int64 anyway, so this just moves the conversion from int64
  to base::Time earlier, making the code more accurately reflect what it
  represents.
- C-style cast in passing int64 to base::Time::FromDoubleT is against the
  style guide, and unnecessary since this is done implicitly by the compiler.
- Fix order of methods in trial_token.cc to match that in trial_token.h
- Use correct style for argument names in trial_token.h (featureName =>
  feature_name).

BUG=590873

Review URL: https://codereview.chromium.org/1752463002

Cr-Commit-Position: refs/heads/master@{#380537}

0 files changed, 0 insertions, 0 deletions