base::Hash: Minor improvements to documentation and testing.

base/hash_unittest.cc

Index: base/hash_unittest.cc
diff --git a/base/hash_unittest.cc b/base/hash_unittest.cc
index 03f9db2ca40d389ba967d584eae3cd39d7352fac..fc8a7519ee98008e439a7c944ec8137fca1759bf 100644
--- a/base/hash_unittest.cc
+++ b/base/hash_unittest.cc
@@ -25,6 +25,16 @@ TEST(HashTest, String) {
   str = "helmo world";
   EXPECT_EQ(1006697176u, Hash(str));
 
+  // Insert a null byte.
+  str = "hello  world";
+  str[5] = '\0';
+  EXPECT_EQ(2319902537u, Hash(str));
+
+  // Test that the bytes after the null contribute to the hash.
+  str = "hello  worle";
+  str[5] = '\0';
+  EXPECT_EQ(553904462u, Hash(str));
+
   // Extremely long string.
   // Also tests strings with high bit set, and null byte.
   std::vector<char> long_string_buffer;