Remove TARGET_PROJECT[_SYSTEM]_INCLUDES

Everything should be getting device specific kernel headers from the
device_kernel_headers header library these days.

This does change the behavior of system libraries on devices using the
VNDK -- they no longer get device-specific kernel headers by default, as
we generally expect the system image to be device-independent. The few
libraries that may still need this can use:

 LOCAL_HEADER_LIBRARIES += device_kernel_headers

Test: treehugger
Change-Id: I90ccb921d58b8d27dd0118a974202696e0af745f
diff --git a/core/config.mk b/core/config.mk
index 69e2b5c..8910c11 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -135,6 +135,12 @@
   LOCAL_IS_AUX_MODULE \
   ,AUX support has been removed)
 $(KATI_obsolete_var HOST_OUT_TEST_CONFIG TARGET_OUT_TEST_CONFIG LOCAL_TEST_CONFIG_OPTIONS)
+$(KATI_obsolete_var \
+  TARGET_PROJECT_INCLUDES \
+  2ND_TARGET_PROJECT_INCLUDES \
+  TARGET_PROJECT_SYSTEM_INCLUDES \
+  2ND_TARGET_PROJECT_SYSTEM_INCLUDES \
+  ,Project include variables have been removed)
 
 # Used to force goals to build.  Only use for conditionally defined goals.
 .PHONY: FORCE
@@ -1057,16 +1063,6 @@
 RELATIVE_PWD :=
 endif
 
-TARGET_PROJECT_INCLUDES :=
-TARGET_PROJECT_SYSTEM_INCLUDES := \
-		$(TARGET_DEVICE_KERNEL_HEADERS) $(TARGET_BOARD_KERNEL_HEADERS) \
-		$(TARGET_PRODUCT_KERNEL_HEADERS)
-
-ifdef TARGET_2ND_ARCH
-$(TARGET_2ND_ARCH_VAR_PREFIX)TARGET_PROJECT_INCLUDES := $(TARGET_PROJECT_INCLUDES)
-$(TARGET_2ND_ARCH_VAR_PREFIX)TARGET_PROJECT_SYSTEM_INCLUDES := $(TARGET_PROJECT_SYSTEM_INCLUDES)
-endif
-
 # Flags for DEX2OAT
 first_non_empty_of_three = $(if $(1),$(1),$(if $(2),$(2),$(3)))
 DEX2OAT_TARGET_ARCH := $(TARGET_ARCH)