[Android WebView] Fix a couple of typos

Fix a couple of typos in variable names/commentary introduced in:
https://codereview.chromium.org/1315633003/

No functional effect.

BUG=156062

Review URL: https://codereview.chromium.org/1331943002

Cr-Commit-Position: refs/heads/master@{#348175}
void AwMainDelegate::ProcessExiting(const std::string& process_type) {

  logging::CloseLogFile();
}

void AwMainDelegate::ProcessExiting(const std::string& process_type) {

  logging::CloseLogFile();
}
