Skip BootloaderMessageTest, UncryptTest for devices without /misc

Skip these two tests if /misc partition is not found in fstab.

Bug: 35712836
Test: Both test skip correctly if there's no /misc in fstab.${hardware}.
Change-Id: I38417a8677030229a335e43eaef85ae70c4e0845
diff --git a/tests/common/component_test_util.h b/tests/common/component_test_util.h
new file mode 100644
index 0000000..4432297
--- /dev/null
+++ b/tests/common/component_test_util.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agree to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _COMPONENT_TEST_UTIL_H
+#define _COMPONENT_TEST_UTIL_H
+
+#include <string>
+
+#include <android-base/properties.h>
+#include <fs_mgr.h>
+
+// Check if the /misc entry exists in the fstab.
+static bool parse_misc() {
+  // The fstab path is "/fstab.${ro.hardware}".
+  std::string ro_hardware = android::base::GetProperty("ro.hardware", "");
+  if (ro_hardware.empty()) {
+    GTEST_LOG_(INFO) << "Failed to get ro.hardware.";
+    return false;
+  }
+
+  std::string fstab_path = "/fstab." + ro_hardware;
+  fstab* fstab = fs_mgr_read_fstab(fstab_path.c_str());
+  if (fstab == nullptr) {
+    GTEST_LOG_(INFO) << "Failed to read " << fstab_path;
+    return false;
+  }
+
+  fstab_rec* record = fs_mgr_get_entry_for_mount_point(fstab, "/misc");
+  if (record == nullptr) {
+    GTEST_LOG_(INFO) << "Failed to find /misc in fstab.";
+    return false;
+  }
+  return true;
+}
+
+#endif //_COMPONENT_TEST_UTIL_H
+