Create FieldTrials class for setting the field trials from a string
in a program. We can later e.g add a builder class where one
can add key/value pairs.
This class is supposed to replace
webrtc::field_trial::InitFieldTrialsFromString.
No-Try: True
Bug: webrtc:10335
Change-Id: I17f45e401102fddda50ca7c4a04bea2f1cb87788
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/256973
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36376}
Note that api/ code is not exempt from the “.h and .cc files come in
pairs” rule, so if you declare something in api/path/to/foo.h, it should be
defined in api/path/to/foo.cc.
Headers in api/ should, if possible, not #include headers outside api/.
It’s not always possible to avoid this, but be aware that it adds to a small
mountain of technical debt that we’re trying to shrink.
.cc files in api/, on the other hand, are free to #include headers
outside api/.
That is, the preferred way for api/ code to access non-api/ code is to call
it from a .cc file, so that users of our API headers won’t transitively
#include non-public headers.
For headers in api/ that need to refer to non-public types, forward
declarations are often a lesser evil than including non-public header files. The
usual rules still apply, though.
.cc files in api/ should preferably be kept reasonably small. If a
substantial implementation is needed, consider putting it with our non-public
code, and just call it from the api/.cc file.