Tag cuj metrics data
Allow tagging a set of cuj runs such that comparisons can be made, e.g.
BEFORE and AFTER certain optimizations are implemented
if we ran
`incremental_build.sh -c "modify Android.bp" --tag BEFORE -b prod`
and then
`incremental_build.sh -c "modify Android.bp" --tag AFTER -b prod`
We'd get the summarized metrics as follows:
```
cuj MIXED_PROD:BEFORE MIXED_PROD:AFTER
no change WARMUP 00:05 00:05
modify Android.bp 00:34 00:30
revert Android.bp 00:36 00:32
```
instead of modifying the values on the `cuj` column. That makes comparison easier and also facilitates a more intuitive graphical plot generation.
Previously the summary would have looked like this:
```
cuj MIXED_PROD
no change WARMUP BEFORE 00:05
modify Android.bp BEFORE 00:34
revert Android.bp BEFORE 00:36
no change WARMUP AFTER 00:05
modify Android.bp AFTER 00:30
revert Android.bp AFTER 00:32
```
Test: incremental_build.sh --tag HI ...
Bug: 239044236
Change-Id: Ie99baa2c277875fa712a53519d5cb8b1fba7f22a
4 files changed
