Resubmit: Add real file for AdNetworks DB

chrome/browser/extensions/activity_log/hashed_ad_network_database.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/activity_log/hashed_ad_network_database.h"
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
 #include "crypto/secure_hash.h"
@@ skipping 13 matching lines @@
 //    worth the (very small) amount of noise.
 // 3. It fits nicely into a int64.
 const size_t kUrlHashSize = 8u;
 COMPILE_ASSERT(kUrlHashSize <= sizeof(int64), url_hashes_must_fit_into_a_int64);
 
 const size_t kChecksumHashSize = 32u;
 
 }  // namespace
 
 HashedAdNetworkDatabase::HashedAdNetworkDatabase(
-    scoped_refptr<base::RefCountedStaticMemory> entries_memory) {
+    scoped_refptr<base::RefCountedStaticMemory> entries_memory)
+    : is_valid_(false) {
   // This can legitimately happen in unit tests.
   if (!entries_memory)
     return;
 
   const size_t size = entries_memory->size();
   const unsigned char* const front = entries_memory->front();
   if (size < kChecksumHashSize ||
       (size - kChecksumHashSize) % kUrlHashSize != 0) {
     NOTREACHED();
     return;
@@ skipping 15 matching lines @@
   }
 
   // Construct and insert all hashes.
   for (const unsigned char* index = front + kChecksumHashSize;
        index < front + size;
        index += kUrlHashSize) {
     int64 value = 0;
     memcpy(&value, index, kUrlHashSize);
     entries_.insert(value);
   }
+
+  is_valid_ = true;
 }
 
 HashedAdNetworkDatabase::~HashedAdNetworkDatabase() {}
 
 bool HashedAdNetworkDatabase::IsAdNetwork(const GURL& url) const {
   int64 hash = 0;
   crypto::SHA256HashString(url.host(), &hash, sizeof(hash));
   // If initialization failed (most likely because this is a unittest), then
   // |entries_| is never populated and we are guaranteed to return false - which
   // is desired default behavior.
   return entries_.count(hash) != 0;
 }
 
 }  // namespace extensions