avoid GCC content::CacheStorage::kSizeUnknown redeclaration error

content/browser/cache_storage/cache_storage.cc

Index: content/browser/cache_storage/cache_storage.cc
diff --git a/content/browser/cache_storage/cache_storage.cc b/content/browser/cache_storage/cache_storage.cc
index d32fc3d96b9af3e54d9e5920c0f75415ff27e574..36e533b81e0b907e47f16d5816bb743fc86e18fb 100644
--- a/content/browser/cache_storage/cache_storage.cc
+++ b/content/browser/cache_storage/cache_storage.cc
@@ -59,7 +59,6 @@ void DoNothingWithBool(bool success) {}
 }  // namespace
 
 const char CacheStorage::kIndexFileName[] = "index.txt";
-const int64_t CacheStorage::kSizeUnknown;

[jkarlin, 2017/01/03 13:06:25]

Can this gcc issue be fixed by changing this const to constexpr?

[Mostyn Bramley-Moore, 2017/01/04 00:11:13]

Seems to work.  CQ dry run underway to confirm.

 
 struct CacheStorage::CacheMatchResponse {
   CacheMatchResponse() = default;
@@ -278,7 +277,7 @@ class CacheStorage::SimpleCacheLoader : public CacheStorage::CacheLoader {
     }
 
     cache_name_to_cache_dir_[cache_name] = cache_dir;
-    callback.Run(CreateCache(cache_name, CacheStorage::kSizeUnknown));
+    callback.Run(CreateCache(cache_name, kCacheStorageSizeUnknown));
   }
 
   void CleanUpDeletedCache(CacheStorageCache* cache) override {
@@ -314,7 +313,7 @@ class CacheStorage::SimpleCacheLoader : public CacheStorage::CacheLoader {
       proto::CacheStorageIndex::Cache* index_cache = protobuf_index.add_cache();
       index_cache->set_name(cache_metadata.name);
       index_cache->set_cache_dir(cache_name_to_cache_dir_[cache_metadata.name]);
-      if (cache_metadata.size == CacheStorage::kSizeUnknown)
+      if (cache_metadata.size == kCacheStorageSizeUnknown)
         index_cache->clear_size();
       else
         index_cache->set_size(cache_metadata.size);
@@ -370,7 +369,7 @@ class CacheStorage::SimpleCacheLoader : public CacheStorage::CacheLoader {
       const proto::CacheStorageIndex::Cache& cache = protobuf_index.cache(i);
       DCHECK(cache.has_cache_dir());
       int64_t cache_size =
-          cache.has_size() ? cache.size() : CacheStorage::kSizeUnknown;
+          cache.has_size() ? cache.size() : kCacheStorageSizeUnknown;
       index->Insert(CacheStorageIndex::CacheMetadata(cache.name(), cache_size));
       cache_name_to_cache_dir_[cache.name()] = cache.cache_dir();
       cache_dirs->insert(cache.cache_dir());
@@ -1072,7 +1071,7 @@ void CacheStorage::SizeImpl(const SizeCallback& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   DCHECK(initialized_);
 
-  if (cache_index_->GetStorageSize() != kSizeUnknown) {
+  if (cache_index_->GetStorageSize() != kCacheStorageSizeUnknown) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(callback, cache_index_->GetStorageSize()));
     return;
@@ -1087,7 +1086,7 @@ void CacheStorage::SizeImpl(const SizeCallback& callback) {
                  base::Passed(std::move(accumulator)), callback));
 
   for (const auto& cache_metadata : cache_index_->ordered_cache_metadata()) {
-    if (cache_metadata.size != CacheStorage::kSizeUnknown) {
+    if (cache_metadata.size != kCacheStorageSizeUnknown) {
       *accumulator_ptr += cache_metadata.size;
       barrier_closure.Run();
       continue;