Add metrics for the combined usage of cookies and cache deletion options.
Note that the total number of uses can be derived by subtracting the usage of both from the existing individual metrics ClearBrowsingData_Cookies and ClearBrowsingData_Cache. However, the number of unique uses can not be derived this way, thus we also need separate metrics for deletion of one data type without the other.
BUG=514592
Review URL: https://codereview.chromium.org/
1259953003
Cr-Commit-Position: refs/heads/master@{#340758}