Include top annotation is a specially formatted comment line providing
the include/inhherit file location hint. E.g., adding
```
```
before
```
$(call inherit-product $(SRC)/foo.mk
```
is a hint to the converter to look for the `foo.mk` files under
`vendor/my_vendor/` in addition to `vendor/google_devices/'
Bug: 193566316
Test: internal
Change-Id: I01c5dde2504f1a9eb724098b1cc03d2176ca2cf9
Old macros (`add_soong_config/namespace` & `add_soong_config_var_value`) are
going away, to be replaced with `soong_config_set`. A new macro,
`soong_config_append` is added to append to the existing value.
Also, flag the attempts to reference the values of the variables in the
Soong config namespace.
Bug: 200297238
Test: internal
Change-Id: Idb6a31632db75d7faef038b83e6a86d9dcf1e736
That is, when a makefile contains
```
ifneq (,$(foo))
$(call inherit-product,module.mk)
endif
```
module.mk has to be present only if `foo` is set.
Fixes: 200163602
Test: internal
Change-Id: Ic5f10ce8d49d6b87162bfe77922bba5e2cce228b
