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 51fb398..1d1078f 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
@@ -92,7 +96,7 @@
     $(warning *    Android.mk for the affected module, and add)
     $(warning *    the LOCAL_MODULE value for that component)
     $(warning *    into the PRODUCT_PACKAGES section of product)
-    $(warning *    makefile(s) where it's necessary, if)
+    $(warning *    makefile(s) where it is necessary, if)
     $(warning *    appropriate.)
     $(warning * )
     $(warning * If the component should be in EVERY build of ALL)
@@ -544,6 +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
 
 
diff --git a/core/definitions.mk b/core/definitions.mk
index c1757f3..6e87cc1 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -55,6 +55,11 @@
 # its sub-variables.)
 ALL_MODULE_NAME_TAGS:=
 
+# All host modules are automatically installed (i.e. outside
+# of the product configuration scheme).  This is a list of the
+# install targets (LOCAL_INSTALLED_MODULE).
+ALL_HOST_INSTALLED_FILES:=
+
 # Full paths to all prebuilt files that will be copied
 # (used to make the dependency on acp)
 ALL_PREBUILT:=
diff --git a/core/main.mk b/core/main.mk
index f7a5193..7e7244e 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -660,6 +660,8 @@
           $(error Module '$(m)' in PRODUCT_PACKAGES has nothing to install!)))
 endif
 
+# Install all of the host modules
+modules_to_install += $(sort $(modules_to_install) $(ALL_HOST_INSTALLED_FILES))
 
 # build/core/Makefile contains extra stuff that we don't want to pollute this
 # top-level makefile with.  It expects that ALL_DEFAULT_INSTALLED_MODULES