Require targets to explicitly import pigweed variable definitions. This
moves out some necessary logic from the BUILDCONFIG.gn file.
Change-Id: If9c9fe5a680cc9d897a0e8a55889873be618ed84
This change replaces the implicit overrides of the default GN target
types in BUILDCONFIG.gn with explicit pw_* versions. This is done to
allow Pigweed to build within larger GN projects without modifying their
BUILDCONFIG files.
Change-Id: I1d1e41d5e9bde8fe076f7031f3c2b98b9630ff70
The pw_result module defines a Result type which stores a Status
alongside some data. It is provided as a convenient way to return a
value and a status together, without requiring an "out" pointer.
Change-Id: Ibb630c7167faf6832e2b5e943220250ac820604e
