Add transport security state generator tests.

net/tools/transport_security_state_generator/trie/trie_writer.h

Index: net/tools/transport_security_state_generator/trie/trie_writer.h
diff --git a/net/tools/transport_security_state_generator/trie/trie_writer.h b/net/tools/transport_security_state_generator/trie/trie_writer.h
index 93fce3624f7193f8c5f281aaf643981d1b8372c3..e1147e23da1db41ac16ae455eb3e7ff85045b5bb 100644
--- a/net/tools/transport_security_state_generator/trie/trie_writer.h
+++ b/net/tools/transport_security_state_generator/trie/trie_writer.h
@@ -8,6 +8,7 @@
 #include <string>
 #include <vector>
 
+#include "base/gtest_prod_util.h"
 #include "net/tools/transport_security_state_generator/bit_writer.h"
 #include "net/tools/transport_security_state_generator/huffman/huffman_builder.h"
 #include "net/tools/transport_security_state_generator/transport_security_state_entry.h"
@@ -40,7 +41,8 @@ class TrieWriter {
 
   // Constructs a trie containing all |entries|. The output is written to
   // |buffer_|. Returns the position of the trie root.
-  uint32_t WriteEntries(const TransportSecurityStateEntries& entries);
+  bool WriteEntries(const TransportSecurityStateEntries& entries,
+                    uint32_t* position);
 
   // Returns the position |buffer_| is currently at. The returned value
   // represents the number of bits.
@@ -54,11 +56,16 @@ class TrieWriter {
   const std::vector<uint8_t>& bytes() const { return buffer_.bytes(); }
 
  private:
-  uint32_t WriteDispatchTables(ReversedEntries::iterator start,
-                               ReversedEntries::iterator end);
+  friend class TrieWriterTest;
+  FRIEND_TEST_ALL_PREFIXES(TrieWriterTest, ReverseName);
+  FRIEND_TEST_ALL_PREFIXES(TrieWriterTest, LongestCommonPrefix);
+
+  bool WriteDispatchTables(ReversedEntries::iterator start,
+                           ReversedEntries::iterator end,
+                           uint32_t* position);
 
   // Serializes |*entry| and writes it to |*writer|.
-  void WriteEntry(const TransportSecurityStateEntry* entry,
+  bool WriteEntry(const TransportSecurityStateEntry* entry,
                   TrieBitBuffer* writer);
 
   // Removes the first |length| characters from all entries between |start| and
@@ -69,8 +76,9 @@ class TrieWriter {
 
   // Searches for the longest common prefix for all entries between |start| and
   // |end|.
-  std::vector<uint8_t> LongestCommonPrefix(ReversedEntries::iterator start,
-                                           ReversedEntries::iterator end) const;
+  std::vector<uint8_t> LongestCommonPrefix(
+      ReversedEntries::const_iterator start,
+      ReversedEntries::const_iterator end) const;
 
   // Returns the reversed |hostname| as a vector of bytes. The reversed hostname
   // will be terminated by |kTerminalValue|.