Remove the APP-* goal

I can't find anything still using this, and I'm close to removing the
PRODUCT-* goal.

Test: codesearch (both android and the build configs)
Test: m APP-test
Change-Id: I4efdcdea2bb9ace14632cab35a2a1c7bdc89592f
diff --git a/core/ninja_config.mk b/core/ninja_config.mk
index 694c696..85a7568 100644
--- a/core/ninja_config.mk
+++ b/core/ninja_config.mk
@@ -7,7 +7,7 @@
 KATI_OUTPUT_PATTERNS := $(OUT_DIR)/build%.ninja $(OUT_DIR)/ninja%.sh
 
 # Modifier goals we don't need to pass to Ninja.
-NINJA_EXCLUDE_GOALS := all APP-% PRODUCT-%
+NINJA_EXCLUDE_GOALS := all PRODUCT-%
 
 # A list of goals which affect parsing of makefiles and we need to pass to Kati.
 PARSE_TIME_MAKE_GOALS := \
diff --git a/core/product_config.mk b/core/product_config.mk
index 360c79d..21d6a16 100644
--- a/core/product_config.mk
+++ b/core/product_config.mk
@@ -139,15 +139,7 @@
 ifeq ($(CALLED_FROM_SETUP),true)
 unbundled_goals := $(strip $(filter APP-%,$(MAKECMDGOALS)))
 ifdef unbundled_goals
-  ifneq ($(words $(unbundled_goals)),1)
-    $(error Only one APP-* goal may be specified; saw "$(unbundled_goals)")
-  endif
-  TARGET_BUILD_APPS := $(strip $(subst -, ,$(patsubst APP-%,%,$(unbundled_goals))))
-  ifneq ($(filter droid,$(MAKECMDGOALS)),)
-    override MAKECMDGOALS := $(patsubst $(unbundled_goals),,$(MAKECMDGOALS))
-  else
-    override MAKECMDGOALS := $(patsubst $(unbundled_goals),droid,$(MAKECMDGOALS))
-  endif
+  $(error The APP-* goal is no longer supported. Use `TARGET_BUILD_APPS="<app>" m droid` instead)
 endif # unbundled_goals
 endif