Don't give the user tag to host modules automatically.

Change-Id: I12d0a84786e5bf2224efd8684526b6097e6105d7
diff --git a/core/base_rules.mk b/core/base_rules.mk
index 09c2586..5f7634e 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -58,14 +58,18 @@
 LOCAL_UNINSTALLABLE_MODULE := $(strip $(LOCAL_UNINSTALLABLE_MODULE))
 LOCAL_MODULE_TAGS := $(sort $(LOCAL_MODULE_TAGS))
 ifeq (,$(LOCAL_MODULE_TAGS))
-ifeq (true,$(LOCAL_UNINSTALLABLE_MODULE))
-LOCAL_MODULE_TAGS := optional
-else
-# Installable modules without tags fall back to user (which is changed to user eng below)
-LOCAL_MODULE_TAGS := user
+  ifeq (true,$(LOCAL_UNINSTALLABLE_MODULE))
+    LOCAL_MODULE_TAGS := optional
+  else
+    ifneq ($(LOCAL_IS_HOST_MODULE),true)
+      # Installable target modules without tags fall back to user (which is changed to user eng
+      # below)
+      LOCAL_MODULE_TAGS := user
+    endif
+  endif
+  #$(warning default tags: $(lastword $(filter-out config/% out/%,$(MAKEFILE_LIST))))
 endif
-#$(warning default tags: $(lastword $(filter-out config/% out/%,$(MAKEFILE_LIST))))
-endif
+
 
 # Only the tags mentioned in this test are expected to be set by module
 # makefiles. Anything else is either a typo or a source of unexpected
@@ -93,6 +97,7 @@
     $(warning *    the LOCAL_MODULE value for that component)
     $(warning *    into the PRODUCT_PACKAGES section of product)
     $(warning *    makefile(s) where necessary, if appropriate.)
+    $(warning *    appropriate.)
     $(warning * )
     $(warning * If the component should be in EVERY build of ALL)
     $(warning * products, then add its LOCAL_MODULE value to the)
@@ -543,6 +548,17 @@
 $(LOCAL_INSTALLED_MODULE) : $(installed_odex)
 endif
 
+# All host modules that are not tagged with optional are automatically installed.
+# Save the installed files in ALL_HOST_INSTALLED_FILES.
+ifeq ($(LOCAL_IS_HOST_MODULE),true)
+  ifneq ($(filter optional,$(LOCAL_MODULE_TAGS)),optional)
+    ALL_HOST_INSTALLED_FILES += $(LOCAL_INSTALLED_MODULE)
+  endif
+  ifneq ($(filter user debug eng tests, $(LOCAL_MODULE_TAGS)),)
+    $(error $(LOCAL_MODULE_MAKEFILE): Module "$(LOCAL_MODULE)" has useless module tags: $(filter user debug eng tests, $(LOCAL_MODULE_TAGS)). It will be installed anyway.)
+  endif
+endif
+
 endif # !LOCAL_UNINSTALLABLE_MODULE