Move fontchain_lint to build/core/tasks

Because `system.img` is a dependency of `fontchain_lint`, and
`system.img` is currently not generated inside `Soong`, it is not
possible to directly convert `fontchain_lint` to `Android.bp`.
Move it to build/core/task first.

Bug: 319050958
Test: m fontchain_lint
Change-Id: Iad483117a609786ecfb885b13015f18dda113155

data/fonts/Android.bp

@@ -57,3 +57,9 @@ prebuilt_etc {
     name: "font_fallback.xml",
     src: "font_fallback.xml",
 }
+
+/////////////////////////////////
+// Move `fontchain_lint` to `core/tasks/fontchain_lint.mk`.
+// Because `system.img` is a dependency of `fontchain_lint`, it cannot be
+// converted to Android.bp for now.
+// After system.img can be generated by Soong, then it can be converted to Android.bp.

data/fonts/Android.mk

-# Copyright (C) 2011 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-LOCAL_PATH := $(call my-dir)
-
-# Run sanity tests on fonts on checkbuild
-checkbuild: fontchain_lint
-
-FONTCHAIN_LINTER := $(HOST_OUT_EXECUTABLES)/fontchain_linter
-ifeq ($(MINIMAL_FONT_FOOTPRINT),true)
-CHECK_EMOJI := false
-else
-CHECK_EMOJI := true
-endif
-
-fontchain_lint_timestamp := $(call intermediates-dir-for,PACKAGING,fontchain_lint)/stamp
-
-.PHONY: fontchain_lint
-fontchain_lint: $(fontchain_lint_timestamp)
-
-fontchain_lint_deps := \
-    external/unicode/DerivedAge.txt \
-    external/unicode/emoji-data.txt \
-    external/unicode/emoji-sequences.txt \
-    external/unicode/emoji-variation-sequences.txt \
-    external/unicode/emoji-zwj-sequences.txt \
-    external/unicode/additions/emoji-data.txt \
-    external/unicode/additions/emoji-sequences.txt \
-    external/unicode/additions/emoji-zwj-sequences.txt \
-
-$(fontchain_lint_timestamp): $(FONTCHAIN_LINTER) $(TARGET_OUT)/etc/fonts.xml $(PRODUCT_OUT)/system.img $(fontchain_lint_deps)
-	@echo Running fontchain lint
-	$(FONTCHAIN_LINTER) $(TARGET_OUT) $(CHECK_EMOJI) external/unicode
-	touch $@