commit f43f2d5ddbb73f90fce16046fa19db4d122d7930
author Daniele Di Proietto <ddiproietto@google.com> Thu Mar 21 18:52:56 2024 +0000
committer Daniele Di Proietto <ddiproietto@google.com> Fri Mar 22 11:21:29 2024 +0000
tree 502f12296163e59bbed440116035f53aaf53ace9
parent f51864ac82ce371f1c639f298452645e8cbd57e7

track_event: Refuse to compile with possibly dynamic strings

https://perfetto.dev/docs/instrumentation/track-events#dynamic-event-names
says:

```
Ideally all event name should be compile time string constants. [...] If
we pass a dynamic string here, we will get compile time static_assert
failure
```

This used to be true before 3a1ed6fb6ab8("Add TraceForCategory* methods
for legacy macros"), but in that commit we broke the static_assert
mechanism (2023-03-20).

Inside PERFETTO_INTERNAL_TRACK_EVENT_WITH_METHOD, there's a
::perfetto::internal::ValidateEventNameType that's supposed to check if
the event name makes sense (either compile time constant or dynamic
string).

The problem is that we call DecayEventNameType() before calling
PERFETTO_INTERNAL_TRACK_EVENT_WITH_METHOD, so
::perfetto::internal::ValidateEventNameType only sees the decayed type.

This commit restores the mechanism for non legacy macro. For legacy
macros we have a test with:

```
TRACE_EVENT_BEGIN0("test", i % 2 ? "Odd" : "Even")
```

Which would break the static_assert. I guess legacy macros didn't have
that protection. For legacy macro we end up calling DecayEventNameType
twice, but that shouldn't be a problem.

Change-Id: I4c43fcce5d154405ea60388a95a34b9fd9b0fb24