Add a makefile for inclusion by projects using libc++.

Based on external/stlport/libstlport.mk

Change-Id: I2516eb376260cfcc2c6b814be12a26c8f873bf7b

libcxx.mk

@@ -0,0 +1,28 @@
+#
+# Copyright (C) 2014 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.
+#
+
+# To use libc++, "include external/libcxx/libcxx.mk" in your target.
+
+# We put the STL libraries in front of any user libraries, but we need to
+# keep the RTTI stuff in abi/cpp/include in front of our STL headers.
+LOCAL_C_INCLUDES := \
+	$(filter abi/cpp/include,$(LOCAL_C_INCLUDES)) \
+	external/libcxx/include \
+	bionic \
+	bionic/libstdc++/include \
+	$(filter-out abi/cpp/include,$(LOCAL_C_INCLUDES))
+
+LOCAL_SHARED_LIBRARIES += libc++