UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36

Steps to reproduce the problem:
1. Start a timeline profile
2. Run code that creates two user timing measures with the same name whose start/end times overlap.

What is the expected behavior?
The timeline should show two overlapping User Timing measures, A and B, where:
- A starts before the B starts
- A finishes before B finishes

In the test case, the measures with name "same-measure-name" should be the same as measures "a" and "b".

What went wrong?
The measures displayed in the Timeline have their start/end times mixed up:
- One is from the start of A to the end of B
- One is from the end of A to the start of B

In the test case, the measures with name "same-measure-name" are not the same as measures "a" and "b".

Did this work before? N/A 

Chrome version: 67.0.3396.99  Channel: stable
OS Version: OS X 10.12.6
Flash Version: Shockwave Flash 30.0 r0

The measures appear to be correct within the performance API itself (when retrieved via `window.performance.getEntriesByType('measure');`), which makes this seem like it's specific to the Dev Tools.

[
    {
        "name": "a",
        "entryType": "measure",
        "startTime": 118.30000003101304,
        "duration": 206.2999999616295
    },
    {
        "name": "same-measure-name",
        "entryType": "measure",
        "startTime": 118.30000003101304,
        "duration": 206.2999999616295
    },
    {
        "name": "b",
        "entryType": "measure",
        "startTime": 219.90000002551824,
        "duration": 205.79999999608845
    },
    {
        "name": "same-measure-name",
        "entryType": "measure",
        "startTime": 219.90000002551824,
        "duration": 205.79999999608845
    }
]
 

Deleted: Screen Shot 2018-07-19 at 3.58.41 PM.png 24.8 KB

	Screen Shot 2018-07-19 at 3.58.41 PM.png 24.8 KB View Download

Deleted: reduced_test_case.html 1.1 KB

reduced_test_case.html 1.1 KB View Download