Log the size of each of the stores and complete DB on launch and after each

components/safe_browsing_db/v4_store.cc

Index: components/safe_browsing_db/v4_store.cc
diff --git a/components/safe_browsing_db/v4_store.cc b/components/safe_browsing_db/v4_store.cc
index 49ec3c51c711aa82d61d27aba9858de31c9c526f..b8882588bfb3f00f0387a3a4a5831ca4840e80f6 100644
--- a/components/safe_browsing_db/v4_store.cc
+++ b/components/safe_browsing_db/v4_store.cc
@@ -196,7 +196,7 @@ void V4Store::Initialize() {
 
 V4Store::V4Store(const scoped_refptr<base::SequencedTaskRunner>& task_runner,
                  const base::FilePath& store_path)
-    : store_path_(store_path), task_runner_(task_runner) {}
+    : file_size_(0), store_path_(store_path), task_runner_(task_runner) {}
 
 V4Store::~V4Store() {
   DCHECK(task_runner_->RunsTasksOnCurrentThread());
@@ -700,11 +700,12 @@ StoreReadResult V4Store::ReadFromDisk() {
     return HASH_PREFIX_MAP_GENERATION_FAILURE;
   }
   RecordApplyUpdateTime(kReadFromDisk, TimeTicks::Now() - before, store_path_);
+  file_size_ = V4ProtocolManagerUtil::GetFileSizeOrZero(store_path_);

[Scott Hess - ex-Googler, 2016/10/21 23:36:45]

Could you get this from contents.size()?

[vakh (use Gerrit instead), 2016/10/24 19:39:32]

Done.

 
   return READ_SUCCESS;
 }
 
-StoreWriteResult V4Store::WriteToDisk(const Checksum& checksum) const {
+StoreWriteResult V4Store::WriteToDisk(const Checksum& checksum) {
   V4StoreFileFormat file_format;
   ListUpdateResponse* lur = file_format.mutable_list_update_response();
   *(lur->mutable_checksum()) = checksum;
@@ -735,6 +736,8 @@ StoreWriteResult V4Store::WriteToDisk(const Checksum& checksum) const {
     return UNABLE_TO_RENAME_FAILURE;
   }
 
+  file_size_ = V4ProtocolManagerUtil::GetFileSizeOrZero(store_path_);

[Scott Hess - ex-Googler, 2016/10/21 23:36:45]

Could this ever be a different value from |written|?

[If not ... then my other comment about file_size_ being an int64_t switches to
being a size_t.]

[vakh (use Gerrit instead), 2016/10/24 19:39:32]

Done.

+
   return WRITE_SUCCESS;
 }
 
@@ -832,4 +835,17 @@ bool V4Store::VerifyChecksum() {
   return true;
 }
 
+int V4Store::RecordAndReturnFileSize(const std::string& base_metric) {
+  std::string suffix = GetUmaSuffixForStore(store_path_);
+  // Histogram properties as in UMA_HISTOGRAM_COUNTS macro.
+  base::HistogramBase* histogram = base::Histogram::FactoryGet(
+      base_metric + suffix, 1, 1000000, 50,
+      base::HistogramBase::kUmaTargetedHistogramFlag);
+  if (histogram) {
+    const int file_size_kilobytes = static_cast<int>(file_size_ / 1024);
+    histogram->Add(file_size_kilobytes);
+  }
+  return file_size_;
+}
+
 }  // namespace safe_browsing