Add bazel 0.28.1 to third_party

Content of README.google:

URL: https://bazel.build/ (https://github.com/bazelbuild/bazel/releases)
Version: 0.28.1
License: Apache License Version 2.0
License File: https://github.com/bazelbuild/bazel/blob/master/LICENSE

Description:
a fast, scalable, multi-language and extensible build system

Local Modifications:
Extracted like this:

wget https://github.com/bazelbuild/bazel/releases/download/0.28.1/bazel-0.28.1-installer-linux-x86_64.sh
rm -rf third_party/bazel
mkdir third_party/bazel
chmod u+x bazel-0.28.1-installer-linux-x86_64.sh
./bazel-0.28.1-installer-linux-x86_64.sh --prefix=third_party/bazel --skip-uncompress
rm third_party/bazel/bin/bazel
rmdir third_party/bazel/bin

Bug: 134732760
Change-Id: I3826c304e3834ed9ae2f6ed3da12b643e57af35c
diff --git a/.gitignore b/.gitignore
index ad0a018..e7f9b71 100644
--- a/.gitignore
+++ b/.gitignore
@@ -31,6 +31,8 @@
 third_party/android_jar/lib.tar.gz
 third_party/android_jar/lib-v[0-9][0-9]
 third_party/android_jar/lib-v[0-9][0-9].tar.gz
+third_party/bazel
+third_party/bazel.tar.gz
 third_party/benchmarks/kotlin-benches
 third_party/benchmarks/kotlin-benches.tar.gz
 third_party/benchmarks/santa-tracker
diff --git a/third_party/bazel.tar.gz.sha1 b/third_party/bazel.tar.gz.sha1
new file mode 100644
index 0000000..b1968d5
--- /dev/null
+++ b/third_party/bazel.tar.gz.sha1
@@ -0,0 +1 @@
+83891f00eacc568434eb59a43ba2ee31ac5c4342
\ No newline at end of file