Created a unified Android test for coverage.

[ Merge of http://go/wvgerrit/143889 ]

New test binary for generating code coverage information.  Run several
reliable, short runnning unit tests.  Actual test failures do not
affect the result of this test.

Bug: 138941105
Bug: 191681397
Test: Android cdm_coverage_test
Change-Id: I6b74d361a8a0e2896e0489acaa64d264158ecaa4

libwvdrmengine/cdm/test/cdm_test_main.cpp

@@ -1,17 +0,0 @@
-// Copyright 2021 Google LLC. All Rights Reserved. This file and proprietary
-// source code may only be used and distributed under the Widevine License
-// Agreement.
-#include <stdlib.h>
-
-#include "gtest/gtest.h"
-
-#include "log.h"
-
-int main(int argc, char** argv) {
-  LOGI("Running Android CDM tests");
-  testing::InitGoogleTest(&argc, argv);
-  const int status = RUN_ALL_TESTS();
-  LOGD("CDM test complete with status %d", status);
-  exit(status);  // Explicit call to exit() is required for code coverage.
-  return status;
-}