Add .clang-format

am: 9ea355c0

Change-Id: I775dff8b2dd88aaabbaf4634d065c4a243f62d94

.clang-format

+#
+# Copyright (C) 2017 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.
+#
+
+BasedOnStyle: Google
+CommentPragmas: NOLINT:.*
+DerivePointerAlignment: false
+AllowShortFunctionsOnASingleLine: Inline
+ColumnLimit: 100
+TabWidth: 4
+UseTab: Never
+IndentWidth: 4