Create CrashReportDatabase interface, a test, and a Mac implementation.

util/mac/xattr_test.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // 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,
@@ skipping 37 matching lines @@
 
   const base::FilePath& path() const { return path_; }
 
  private:
   ScopedTempDir temp_dir_;
   base::FilePath path_;
 };
 
 const char kKey[] = "com.google.crashpad.test";
 
+TEST_F(Xattr, HasXattr) {
+  EXPECT_FALSE(HasXattr(path(), kKey));
+  EXPECT_TRUE(WriteXattr(path(), kKey, ""));
+  EXPECT_TRUE(HasXattr(path(), kKey));
+}
+
 TEST_F(Xattr, ReadNonExistentXattr) {
   std::string value;
   EXPECT_FALSE(ReadXattr(path(), kKey, &value));
 }
 
 TEST_F(Xattr, WriteAndReadString) {
   std::string value = "hello world";
   EXPECT_TRUE(WriteXattr(path(), kKey, value));
 
   std::string actual;
@@ skipping 45 matching lines @@
 
   expected = std::numeric_limits<time_t>::max();
   EXPECT_TRUE(WriteXattrTimeT(path(), kKey, expected));
   EXPECT_TRUE(ReadXattrTimeT(path(), kKey, &actual));
   EXPECT_EQ(expected, actual);
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace crashpad